Develop Bugs

[Q] Rooting by downgrading from HBOOT 0.92 and advice on custom ROM

Hello
I'm a new member here, altho I've been following a few threads for the latest weeks. Now curiosity has killed the cat....
I'm planing on using the recently uncovered method of downgrading from HBOOT 0.92 to 0.80 (or is it .82?) and apply unrevoked3 to gain root on My Desire as explained in the HOWTO. Phone's unbranded and unlocked, so I don't expect any problems to occur there other than to wipe my phone clean. I've been reading enough to feel reasonably confident in these steps.
But then there is the question of what ROM to put on My Desire when I'm done. I'm totally blank here. I've been looking at the descriptions and threads of a few ROMs in the dev-forum, but I can't say it makes me much smarter, except for a couple of ROMs that definitely isn't for me.
I've been quite happy about the HTC Sense that the phone was shipped with since I bought it back in April. Not much different about the new one that came with the Froyo OTA I updated to last weekend. What annoys me the most is the glitch in the Market that was introduced, and that there seems to be doubles of apps in the ROM, like both android and HTC versions of Facebook and others. Waste of space and waste of resources to have both fire up at boot. Same with a few stock installed apps that start at boot that I never use. Useless
Also I'd like to have that annoying boot sound gone, or maybe replaced by some custom stuff.
I also need the Froyo. The Wi-Fi hotspot and increased performance are must-have. App2sd too, but it looks like most ROMs have some implementation of this that at least matches the functionality of the one included in Froyo.
It's not that I am locked up to be a Sense-user, I just haven't tried anything else and don't know better. Love those 7 screens, altho I use only 6 of them. Also I've grown accustomed to a few of the HTC widgets. Eats a lot of screen real-estate, but looks good imo. Haven't looked up many screenshots of optional screens, so I have really no clue what the options are.
Is it obvious that I should apply a modified/rooted HTC-Sense Froyo ROM, or are there others that would match my needs better? I'm an old Linux user, so I'm not afraid to test new UIs. I'd love to hear from you experienced users what you have to recommend an Android-noob.

I suggest using this rom:
http://forum.xda-developers.com/showthread.php?t=741775
Its the official HTC rooted without hboot 0.92, if you don't like any great modifications, I suggest using this mod.
If you want an other mod, take a look here:
http://forum.xda-developers.com/wiki/index.php?title=HTC_Desire#Unofficial_ROMs

Thanks or the reply. That first one is what I had in mind, but it feels "wrong" to stick with stock when I've finally bothered to crack open the phone
Maybe I should look into just how much work it is to swap ROMs and test out a couple for a few days each? Or is there someone who have written up a nice little review listing some of the most important differences between the modified ROMs?

I decided to go for a LeeDroid ROM. Been playing with it for a few hours, and it seems to do the job well
One happy rooted HTC customer

Try Neophyte 1.6 - much better mate Totally stable and has no issues that other custom roms do

Neophyte looks like a good alternative. Thank you
Also looks from the thread on that one that there is a new version coming one of the first days, so I'll stick with LeeDroid untill then. Looks to be a breeze to swap ROMs as long as you don't bother to install every unusefull app for each swap. And a nice way to clean out the phone of various useless stuff LOL

Brand new with HTC

Well i recently recieved an upgrade with my provider and I opted for the M9. This is because for the last 4 years ive had samsung and although I havent a bad word to say for them, I just fancied a change. So here I am.
Quite a difference in the way you can obtain certain things like unlocking, rooting etc. To be honest, though it was a bit worrying at first, I soon managed to get things done and It sort of makes you feel like you're more involved with your phone. Rather than just letting a .zip do all the work or a full firmware file through odin do the business.
Ive only had it 2 days and managed to root, unlock and s-off, Flashed a new firmware and rom and very happy with it. I have noticed despite the camera being a higher pixel count it isnt quite as sharp as the samsung camera, still good though. The front camera is definately better.
Having only had it 2 days though i cant really comment on performance etc etc. I need it longer but i'm relatively happy with how its going.
I do have a couple of concerns. 1 being the temperature it reaches when flashing etc.My samsung used to feel very warm but obviously its more noticable with the HTC due to it being all metal and I guess thats good as it sucks all the heat into the shell and away from the cpu's.
Anyway, this was just to say hi, and that I hope to continue to enjoy my htc experience, its definately come on a lot since my last HTC many years ago (Wildfire S).
Any tips / tricks / must haves that I should know about?
Thanks and HI! =)

tomorio said:
Well i recently recieved an upgrade with my provider and I opted for the M9. This is because for the last 4 years ive had samsung and although I havent a bad word to say for them, I just fancied a change. So here I am.
Quite a difference in the way you can obtain certain things like unlocking, rooting etc. To be honest, though it was a bit worrying at first, I soon managed to get things done and It sort of makes you feel like you're more involved with your phone. Rather than just letting a .zip do all the work or a full firmware file through odin do the business.
Ive only had it 2 days and managed to root, unlock and s-off, Flashed a new firmware and rom and very happy with it. I have noticed despite the camera being a higher pixel count it isnt quite as sharp as the samsung camera, still good though. The front camera is definately better.
Having only had it 2 days though i cant really comment on performance etc etc. I need it longer but i'm relatively happy with how its going.
I do have a couple of concerns. 1 being the temperature it reaches when flashing etc.My samsung used to feel very warm but obviously its more noticable with the HTC due to it being all metal and I guess thats good as it sucks all the heat into the shell and away from the cpu's.
Anyway, this was just to say hi, and that I hope to continue to enjoy my htc experience, its definately come on a lot since my last HTC many years ago (Wildfire S).
Any tips / tricks / must haves that I should know about?
Thanks and HI! =)
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Click to collapse
Hello. Welcome. I hope you enjoy your M9 experience.
Yeah, they heat up a little bit when flashing, but I think you're assumption on the metal body is correct.
I think the camera is not awesome in lower light situations. outside, it's fantastic. There's a thread on the camera in this forum you should check out, but some people who have used both the S6 and M9 say that the S6 is better in low light situations, but the M9 is better outside. You can probably get some tips in that that thread (http://forum.xda-developers.com/one-m9/general/pictures-m9-t3044267). A lot of people like shooting in manual mode with this phone and can produce some pretty nice results.

jollywhitefoot said:
Hello. Welcome. I hope you enjoy your M9 experience.
Yeah, they heat up a little bit when flashing, but I think you're assumption on the metal body is correct.
I think the camera is not awesome in lower light situations. outside, it's fantastic. There's a thread on the camera in this forum you should check out, but some people who have used both the S6 and M9 say that the S6 is better in low light situations, but the M9 is better outside. You can probably get some tips in that that thread (http://forum.xda-developers.com/one-m9/general/pictures-m9-t3044267). A lot of people like shooting in manual mode with this phone and can produce some pretty nice results.
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Excellent thank you. I'll take a look and see if I can get any tips for improving my pictures. When I was in store chosing my next phone they did mention that it isn't the best in low light, probably due to the smaller aperture but I use take most of my pictures outside or in decent lighting anyway so I suppose it's not an issue as such. I'll definately have a look at that thread though and see if using manual mode will help me out more.
Thanks.
edit - I do have a quick question about firmwares. I have just flashed the 1.40.401.x but also noticed their are some 2.xx.xx something. Which are newer and why the huge difference? lol sorry to ask what is probably a very nooby question.

tomorio said:
Excellent thank you. I'll take a look and see if I can get any tips for improving my pictures. When I was in store chosing my next phone they did mention that it isn't the best in low light, probably due to the smaller aperture but I use take most of my pictures outside or in decent lighting anyway so I suppose it's not an issue as such. I'll definately have a look at that thread though and see if using manual mode will help me out more.
Thanks.
edit - I do have a quick question about firmwares. I have just flashed the 1.40.401.x but also noticed their are some 2.xx.xx something. Which are newer and why the huge difference? lol sorry to ask what is probably a very nooby question.
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Click to collapse
I find it takes pretty decent still life photos in low light, but not great snapshots of people/pets (things that move). I think on auto, the camera isn't aggressive enough in bumping ISO, so it has to use too slow a shutter speed to completely stop movement.
I think 1.40 was kind of a temporary release to quickly address some issues in 1.32 (camera and CPU management mostly)...I don't think it was ever officially released in the US. But 1.40 has issue of it's own, mainly that charging the phone can be extremely slow at times. I don't know how HTC comes up with firmware numbering, but I would guess that part of the big number jump has to do with the fact that 1.xx firmware was for Android 5.0.2 while the 2.7 firmware runs on Android 5.1. I flashed the 2.7 firmware last night and the 1.40 base rom that I use works fine with it so far...I can't say with certainty that your ROM will work with it though. FYI, I'm on InsertCoin.

jollywhitefoot said:
I find it takes pretty decent still life photos in low light, but not great snapshots of people/pets (things that move). I think on auto, the camera isn't aggressive enough in bumping ISO, so it has to use too slow a shutter speed to completely stop movement.
I think 1.40 was kind of a temporary release to quickly address some issues in 1.32 (camera and CPU management mostly)...I don't think it was ever officially released in the US. But 1.40 has issue of it's own, mainly that charging the phone can be extremely slow at times. I don't know how HTC comes up with firmware numbering, but I would guess that part of the big number jump has to do with the fact that 1.xx firmware was for Android 5.0.2 while the 2.7 firmware runs on Android 5.1. I flashed the 2.7 firmware last night and the 1.40 base rom that I use works fine with it so far...I can't say with certainty that your ROM will work with it though. FYI, I'm on InsertCoin.
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Ah I see. I just noticed that most of the roms out at the moment recommend using the 1.40 firmware which is why I flashed that one. I'm currently using Viper which seems good so far, only had it a day. As I was new to everything I thought it best to stick with what is suggested as unlike with my Galaxy s4 the flashing of firmwares and roms seems quite specific. I had noticed it is quite a slow charge process, but I tend to charge overnight if I can and make the phone last the full day so it's not that much of a downer, unless i've had a lot of usage and need a "quick boost" >< then its not so great lol

tomorio said:
Ah I see. I just noticed that most of the roms out at the moment recommend using the 1.40 firmware which is why I flashed that one. I'm currently using Viper which seems good so far, only had it a day. As I was new to everything I thought it best to stick with what is suggested as unlike with my Galaxy s4 the flashing of firmwares and roms seems quite specific. I had noticed it is quite a slow charge process, but I tend to charge overnight if I can and make the phone last the full day so it's not that much of a downer, unless i've had a lot of usage and need a "quick boost" >< then its not so great lol
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Many people have reported that rebooting temporarily fixes the slow charge issue.
MaximusHD is the only rom that uses the new firmware currently. I bet others will be updating soon. The Viper guys have been chatting about Viper 3.0 being released soon and I assume it will be 5.1 based.

Thats good. I'll keep checking any updates and see what happens.
I can't wait for a few more roms to be up and about. I'm used to the countless available for the S4 and forget that device is 2 years old now so there was plenty of time to get things going. I shall just have to be patient.
Thanks for all the help mate.

tomorio said:
Thats good. I'll keep checking any updates and see what happens.
I can't wait for a few more roms to be up and about. I'm used to the countless available for the S4 and forget that device is 2 years old now so there was plenty of time to get things going. I shall just have to be patient.
Thanks for all the help mate.
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Click to collapse
Not a problem. Enjoy the device.

Not to hijack your thread tomorio, but how did you decide on which phone? I have the Galaxy S5 now, but I'm torn between HTC M8, M9, or LG G4. Pros and cons to all. My biggest thing is ease of root as I have a couple of frequent use apps that require it. Thanks in advance for any tips on how you decided!
~Vol

Vol4Ever said:
Not to hijack your thread tomorio, but how did you decide on which phone? I have the Galaxy S5 now, but I'm torn between HTC M8, M9, or LG G4. Pros and cons to all. My biggest thing is ease of root as I have a couple of frequent use apps that require it. Thanks in advance for any tips on how you decided!
~Vol
Click to expand...
Click to collapse
Hijack away my friend.
I too was torn but between the S6, LG G4 and htc m9. I was leaning away from the S6 as I really fancied a change, however I think it will always have more options available to it (for custom roms etc) due to the larger fan base and it is much simpler to get to grips with for rooting etc.
the G4 my Partner already has and something about it when I used it I just didn't enjoy, and its nowhere near as pretty as the M9 lol. Try one out if you can just to see for yourself. Unfortunately I have no more experience of it than having a little play of her phone so unsure on the rooting processes etc but imagine it to be similar to the Samsung way.
The HTC M9 was a tough choice. Especially when I looked at how rooting etc is done (this is one of the first things i check with phones flash-a-holic you see lol). Anyway, once i'd read over all the advice given in this forum, the how to's etc and got a small amount of knowledge of the process of rooting using fastboot etc i pushed myself to make the choice. As far as user friendly goes, I think for simpler flashing the Sammy will always win again, as it's processes are far simpler (flashing via odin etc and all the files being ready to flash straight off the bat). However if you're keen for a change then I would recommend the M9. I've only had it a few days really but already i'm glad I did.
Just be sure to look through all the ways of rooting so that you get a better understanding of how its done. I think once the initial unlocking bootloader, rooting and flashing custom recovery is done it;s pretty simple after that. I've got to grips with it already.
One of the main benefits I found with the sammy phones was I was never worried about bricking because there were many different ways to get it back up and running. I dont know how that fares with the M9 but as long as you follow the instructions step by step and have backups available you should be ok.
Sorry for the wall of text, if you need anything else let me know.
Hope that helps.
- edit- also i may have touched on it in a previous post, but i think as far as customizing your phone goes and making it your own, I feel that HTC as a company are much more in tune with "our world" of people who like to change the stock features and put their own touch on things.

Walls of text don't bother me. I'd rather have too much information than not enough. It's going to be the M9 if we can work out the AT&T issues I mentioned in my other thread. I went to the store last night expecting a simple transaction like the bazillion other phone upgrades I've done over the years. Walked out steaming, to say the least. The worst part was the lady helping me majorly projected a "couldn't care less" attitude that is a major pet peeve of mine!

Thinking of switching from Note 2 to G4

The primary reason I'm considering the G4 instead of any of the new Samsung models is to gain root. If I order the G4 now and it comes with 12a will I be able to root the phone right away?
Thanks,
Update: If the answer is no root for vzw 12a it will cost me $35. I just ordered it - 14 day return policy with $35 restocking fee.
I don't want to install a different ROM. Just gain root so I can run viper4audio, adfree, titanium, greenify (root) and other apps that need root access.

dsteinschneider said:
The primary reason I'm considering the G4 instead of any of the new Samsung models is to gain root. If I order the G4 now and it comes with 12a will I be able to root the phone right away?
Click to expand...
Click to collapse
Verizon pulled the 12A firmware because it screwed up receiving Notifications over WiFi, specifically because of something with IPv6. This is NOT a LG specific issue but rather a Lollipop issue. The Nexus 5 and Samsung devices were hit too. There has been a fix for a while, but for some reason this update did not include those fixes and thus the update was pulled.
If you order a G4, it will come with 11A, which is rootable.
Even in a odd ball chance that you do get one with 12A, that is still rootable.
Although we are in the process of a Bootloader Unlock. At this time the process is only working on V0 devices (10A). Every update increases this version (11A = V1, 12A = V2). This "version" prevents users from flashing backwards. So if you update to 12A, you can not go back to 11A.
What this means is everyone is instructed to NOT update. In the event that they update the bootloader unlock to allow V1 devices, you will already be on V2.
While 12A fixes a few missed touches with the touchscreen (software issue), it ultimately will break ability to receive notifications over WiFi (there is a fix in the Play Store) and could hinder you unable to unlock your bootloader (for flashing custom roms and stuff) moving forward.
The G4 is an awesome device but at this time only the Tmobile and Sprint have custom recoveries. The Verizon is stuck with only root. We CAN "flash" stuff with an app, so things like Xposed and stuff are working. No big deal as there seems to be a lot of people working on this device to crack it open. I just want you to be informed when you make your purchase.
However LG is releasing a new phone coming out, the LG V10. It is basically the same phone but has a second display at the top for quick shortcuts, media controls, etc. So you may want to look into that too. Also the new Nexus Devices have just been release recently, which are other options. Me personally, I would recommend the G4 still. The DoubleTap2Wake/Sleep is so addicting and will change how you use your phone. It also has Wireless Charging (with an addition of a Qi Sticker). The addition of a second display looks pretty cool, but probably will only work with LG specific apps. No one knows if anyone will be able to customize the ability of the second screen. As for the Nexus devices, the 5X and the 6X are a little too small and a little too big for me. The LG Nexus would be my first choice out of the 2015 Nexii. However the LG software is very very cool. It is AOSP enough but has very useful little changes that will be missed on a bland AOSP rom (floating dialer, messaging, clip board, etc). Also DoubleTap2Wake is finicky on the AOSP roms. So if you desire the need to use AOSP, go with one of the Nexus. If you are sold on the G4 (like I am) then just do it. You'll be good.
UPDATE:
Just saw your Ninja edit with making the purchase. Worry not. Welcome to the community.

Hi player911,
Thanks for the great welcome to the LG G4 community! I did make the decision to not worry about the V10 and appreciate your opinion on that. I'm excited about the phone, I've been on the Note 2 forever. Didn't use the stylus much (the times I did to make quick notes I can instead just use pen and paper and "scan" it with the camera into OneNote.) Verizon already shipped it Fedex, will probably get it Monday.
Doug

What's going to be your next device?

My deepest apologies if this is in the wrong place, but I need to ask this question some place. If this has been asked before, the search did not return anything that caught my eye, please feel free to point me in the correct direction! Considering that I have Verizon as a carrier and live in the US, I thought I would ask this audience to see what device has caught your eye!
My upgrade date is drawing near and I need to decide on a device that I want to give a shot next, and I would like to avoid being disappointed in my next device.
What is your next device going to be, and why?
I have been keeping my eye on the newest Nexus (now the Pixel) phones, but I really can't see myself giving up my sd card slot. I am also kind of partial to the removable battery.
I really like this phone, but the development has been poor due to Verizon's locked bootloader. I have a feeling this will be the case with ALL Verizon phones, but I have unlocked bootloaders in the past (Even my Note 3 finally got a bootloader unlock!).
My real pull to the Nexus/Pixel was the fact that it's a Google phone, it gets the latest Operating System updates, and AFAIK they were able to unlock the bootloader in the past (please correct me if I am wrong, as I have not really ever owned a Nexus device).
I really enjoy the ability to install a custom Rom and modify the OS (I LOATHE the stock DPI on most devices!!!) and I can't exactly get tethering on my package (but there is usually an app for that ). I would like to find something powerful enough to keep me happy for the next few months, because lets face it, we all start to long for a new device.
Thank you for your time and consideration!

b3y0ndd34th said:
My deepest apologies if this is in the wrong place, but I need to ask this question some place. If this has been asked before, the search did not return anything that caught my eye, please feel free to point me in the correct direction! Considering that I have Verizon as a carrier and live in the US, I thought I would ask this audience to see what device has caught your eye!
My upgrade date is drawing near and I need to decide on a device that I want to give a shot next, and I would like to avoid being disappointed in my next device.
What is your next device going to be, and why?
I have been keeping my eye on the newest Nexus (now the Pixel) phones, but I really can't see myself giving up my sd card slot. I am also kind of partial to the removable battery.
I really like this phone, but the development has been poor due to Verizon's locked bootloader. I have a feeling this will be the case with ALL Verizon phones, but I have unlocked bootloaders in the past (Even my Note 3 finally got a bootloader unlock!).
My real pull to the Nexus/Pixel was the fact that it's a Google phone, it gets the latest Operating System updates, and AFAIK they were able to unlock the bootloader in the past (please correct me if I am wrong, as I have not really ever owned a Nexus device).
I really enjoy the ability to install a custom Rom and modify the OS (I LOATHE the stock DPI on most devices!!!) and I can't exactly get tethering on my package (but there is usually an app for that ). I would like to find something powerful enough to keep me happy for the next few months, because lets face it, we all start to long for a new device.
Thank you for your time and consideration!
Click to expand...
Click to collapse
I had the G4 for over a year and just upgraded to the HTC 10

pettigrew95 said:
I had the G4 for over a year and just upgraded to the HTC 10
Click to expand...
Click to collapse
How are you liking it? And how is the development?
Are you a heavy phone user? What is the battery life like?

b3y0ndd34th said:
How are you liking it? And how is the development?
Are you a heavy phone user? What is the battery life like?
Click to expand...
Click to collapse
The phone itself is awesome but I'm having some battery issues and trying to pinpoint what is causing the poor battery life. Development is fantastic since S-OFF and root were achieved via the Sunshine APK. There are tons of ROMs and kernels to flash. I miss having a removable battery but the HTC 10 does have a micro-SD slot.

I'm not in the market for a new phone to replace my G4 yet, but after getting a bootloop replacement with the first gen manufacturing date, I probably will be looking sooner rather than later. I get to stay on the unlimited data family share plan through a corporate discount, so I'm kind of curious if VZW still subsidizes new phones on those lines. If so, I'd miss out on the savings if I were to get a Pixel, which I presume will only be offered at full price. I've been out of the loop since MM came out and made it harder to mod Android, so it's good to see that at least there are some non-developer version phones out there still.

HTC One M9 Variants to avoid buying (rooting, bootloader unlock, s off)?

My LG G4 is dead and i need a good substitute ASAP on a tight budget ($200-$250 max). This pretty much limits me to 2015 era phones. Not getting another LG, Samsungs are too expensive and S6 has no microSD slot anyway. Narrowed it down to either an HTC One M9 and Moto X Force. Moto's limited development as well as an alarming number of nightmarish defective OLED displays has scared me off of it (shame as I love OLEDs).
So i'm about settled on an HTC One M9. I did my best to research any deal breaking hardware defects, any problems seem far less severe or common compared to G4 or Moto. Assuming I haven't missed anything...
So that said my question now turns to the software side- are there any carriers/variants of the M9 I should try to avoid buying? As the title says, I wish to unlock the bootloader, root, and eventually install custom roms etc. I'm prepared to pay for Sunshine if necessary provided all M9 variants are supported. I've done my best to read through as many threads and pages as I could before asking this. It SEEMS like i'd be safe buying pretty much any M9 and still be able to unlock bootloader, root and s off. Even Verizon models if i'm not mistaken? Am I correct in this assumption? I wanted to ask just to ensure I didn't miss any important caveats before buying.
I messed up buying an LG, many suffer from a motherboard defect causing unfixable bootlooping and mine finally succumbed the other day. Mine was also a region that didn't allow bootloader unlocking. I could root with some effort if I didn't mind being stuck forever on lollipop, but no custom roms and other annoying limitations.
I don't wish to repeat the same mistakes if I can avoid it, so any information regarding my query would be greatly appreciated. Any other advice or things to look out for regarding the M9 would be helpful too. Thanks very much in advance.
By the way, the version i'm looking at buying is listed as an AT&T model. From what I have seen, this variant seems to be pretty much perfect for doing all I want. But I still wanted to ask this in case I either get a different variant, or if the seller is listing the wrong version of the product. If all M9s are basically equal at this point, then I don't need to worry which kind I get.

Try to buy a worldwide edition. It's the sim unlocked from factory with region 401 ie x.xx.401.xx firmware version.
M9 is a solid phone. The camera isn't the greatest but it does take good shots. It can get a bit hot if charging and playing games at the same time and it is more than capable of draining the battery in an hour or two if you use resource intensive games or apps. The sound is very clear and boomsound is a major player in the satisfaction this phone gives, making the speakers significantly bassier than other devices on the market. The speakers 'can' be a little quiet at full but they ALWAYS stay crystal clear with no distortion at all.
You MUST get a protector case for this device as the front of the actual phone can crack if you apply pressure, by the front camera lens is cracked on mine. Tech21 make a good sturdy case for this device but it is a tad expensive at £30 GBP.
I Don't recommend using custom roms with this device as not only is the risk of a brick significantly higher it is also going to result in a slightly slower phone than stock rooted.
The different variants of this device are essentially the same but carrier locked versions can be a prick to find software to fix stuff.
In all you've made the right choice of phone if you plan on keeping it stock but the wrong one if you plan on modding it.
Beamed in by telepathy.

Sorry, but I have to disagree with some points of the post above this one.
If you live in the US then choosing either the unlocked/dev variant or the version of your carrier is the best choice. SKU 401 is optimized for the EU (in regard to supported frequencies and some GPS configurations). And it's important that you choose the correct hardware version for your carrier's technology (Verizon & Sprint: CDMA - all other variants: GSM). The firmware of CDMA devices and GSM devices isn't interchangeable. You can't even flash Sprint firmware on a Verizon device (or vice versa) without damaging it. However, you can change from one GSM firmware to a different one if you want to (S-OFF required).
Just for having it mentioned (I know that you don't need this information but who knows who else is going to read this): The Verizon version's bootloader cannot get unlocked via HTCdev (unlike the bootloader of all other versions). You need S-OFF for unlocking the bootloader of that version. Since sunshine needs root on the latest firmware version the only way to unlock the Verizon variant on the latest firmware is an xtc clip/java card. (This may change with a future update of sunshine.) Or you try to get a pre-Nougat Verizon M9 and use the temp-root of the sunshine app.
In addition, HTC provides RUUs for its US devices. Therefore, getting back to stock is easier with one of them than with all other non-US variants.
And in regard to custom roms: They don't hardbrick your device. The worst thing that can happen is a soft-brick/bootloop and that will only happen if you try to flash a custom rom whose base is newer than your phone's firmware (and some nougat roms are even compatible with the marshmallow firmware so this happens quite rarely in the recent time).
Aside from that, my phone is as fast while I use Viper 6.1 as it has been while I was playing around with the stock rom. If there really is a difference then you need laboratory equipment for being able to detect it. And I'm pretty sure that you get the same performance on other (sense-based) custom roms, as well.
The only thing that you need to be aware of is that there are more and more reports of dying memory chips. These nand deaths happen on stock phones and on modified phones. As far as I read, no one has been able to repair such a dead device except for HTC itself. I don't know what's the cause of the problem since I know enough people whose M9's are still working fine without any issues.
Sent from my HTC One M9 using XDA Labs

Thanks for the reply from both of you. I'm surprised and happy a mod actually replied too!
My LG was locked out from installing custom roms and such, but I have experience installing some on a first gen Galaxy S (currently using it as backup in fact). I'm sure things have changed somewhat, but I am aware of the potential risks in flashing custom roms. I've bootlooped and soft bricked my device doing so more than once. I'm not a programmer, but I was able to fix them all with patience, research and the right tools/software. I assume there are also methods to deal with soft bricks and bootloops on HTC One M9 if you consider it less of a threat than a hardware brick (which my LG G4 got even without flashing anything). I appreciate the warning and advice either way.
I'm not concerned with the carrier compatibility that much. I don't have service with anyone at the moment and can use whatever. Seller says the device is a GSM unlocked AT&T device, if accurate then i'm perfectly content with using GSM networks. Listing says "new AT&T carrier overstock item", which I hope means the device is okay. It's being advertised as running 5.0 Lollipop, which I assume means the stock rom it came with when first released and also hope is an okay starting point for doing whatever rooting and customization I want.
I hope the NAND issue doesn't crop up on the one I get though, that doesn't sound good. HTC attracted me because i've seen fewer people complaining about widespread hardware defects compared to many other phones. It's difficult to find phones that are a good value, are reasonably free of serious problems and include features I deem important (microSD card support for instance, and having reasonably fast processors). My options are limited.
I'm not sure if i'll need s off. I'm new to that term and don't know much about it besides it being some sort of HTC security. Not sure what doors would open up by having s off, still researching. Assuming the model I buy is accurately listed as AT&T, it sounds like I should be able to unlock the bootloader, root, flash TWRP and even get custom roms without having s off. Am I correct? Not even sure if it's required to flash kernels such as ElementalX.

That can happen if you post in the forum of a device that's owned by a mod. Don't forget that we're normal members, as well, if we don't moderate.
If you face a soft-brick you only need to keep both volume buttons and the power button pressed until the phone reboots to its bootloader. From there on you can boot to TWRP and only need to flash a working rom or to restore a backup of a working (stock) rom and the problem should be fixed. Hard-bricks only happen if you flash a CDMA firmware on a GSM device (or vice versa) or a Sprint firmware on a Verizon device (or vice versa). The phone will still be booting but from what I observed here on xda your SIM card won't be detected, anymore, even if you re-flash your phone's original firmware. Aside from that you can "kill" this phone if you're impatient while it's installing an update and power it down during the process (there was a time when that happened quite often). Therefore, I suggest you to just let it do it's thing after you started the update process. Depending on which update you want to install it might take up to approximately half an hour and the phone might reboot (and therefore vibrate) several times.
Correct, for flashing custom recoveries/roms/kernels you don't need S-OFF on this phone (as long as it's not the Verizon variant). Take a look at the further reading section of the ReadMe thread. There's an article linked that explains S-OFF. And Sneakyghost's firmware thread in the development section should contain an explanation, as well. If I remember correctly it should be located in the 5th post. Be aware that you don't need to (re-)lock this phones bootloader like you needed to do on older HTC devices if you want to flash a RUU with S-ON as long as you use the SD card method. That's the recommended method, btw.
I personally don't use a custom kernel. They had a huge impact on my last device (the HTC One S - released in 2012) but HTC seems to be learning at least from some of its "mistakes" since the battery optimizations are much better on the M9. Therefore, I haven't been using a custom kernel since one of the early versions of ElementalX. On the other hand, that means that I can't tell you whether the current version got optimized that much that it actually has an impact, again.
In regard to the nand issue: Don't forget that 95% of the posts here get made by people who face problems with their phones whereas most people don't post if everything is working fine. That might cause that an issue seems to be more common than it actually is. And as said in my last post, I haven't seen such a dead nand in real life, yet, and I know a lot of people who own this phone.
And last but not least a little tip: Find out your phone's firmware as soon as you get it. If it's a pre-4.x version (everything before android n) then try to find the latest 3.x RUU for your SKU*. If you install that one you will save some time that would otherwise be needed for installing a huge amount of OTA updates. (A RUU only needs around 5 minutes if you use the SD card method.) You can't directly install a 4.x RUU since HTC changed the encryption keys between firmware 3.x and 4.x. Therefore, you need to install the 4.x update via the software update function of the phone since OTAs aren't encrypted. More information, some useful files and instructions can be found in the ReadMe thread. (It's a big wall-of-text but reading and understanding it is worth the time that you need for doing so.)
Edit: * = Here's a download link for the latest 3.x AT&T M9 RUU (directly from HTC's server). However, now that I think about it I actually can't tell you whether the AT&T variant already received android n...
Sent from my HTC One M9 using XDA Labs