From the GrapheneOS website

8th generation Pixels provide a minimum guarantee of 7 years of support from launch instead of the previous 5 year minimum guarantee

As for issues, the only one I’ve heard really people complain about is the lack of Google Pay. I’ve never used it so it doesn’t make any difference for me. Apparently, some banking apps have issues on GrapheneOS too, but both my banks’ apps work fine.

I wrote about battery drain in response to another user who had issues on Graphene, even though this is a general Pixel issue, and has nothing to do with Graphene. The modem chews through the battery if you don’t have good connectivity, although I’m not sure if that’s still a big problem with the 7’s and 8s. It definitely is with the 6.

Personally, I had problems with adapting to the “don’t try to be a power user” philosophy of Graphene. I was used to flashing ROMs, rooting and customizing the hell out of my previous smartphones. Then I suddenly had a device which just… worked. It’s still an odd feeling, but I got used to it.

Just wanted to add to the other users unique experiences. From the perspective of someone who was a “the only good phone is a phone which is one small mishap away from being bricked” kinda guy

I’ve been using Graphene for a few weeks now. I’m really happy with it. That said, I’m a pretty minimal smartphone user. I don’t use NFC or any AI or Assistant features.

My only hiccup was my banking app didn’t work at first. Luckily their documentation is informative and easy to read. This is a common problem with a simple solution… You just need to change a toggle in the app control setting.

Installation is super easy if you use their web installer - just read through the procedure first, follow it exactly, and be patient. There are a few places where you think it’s done, but if you interrupt it, the install can go sideways.

It’s also easy to revert back to stock if you want to. And it doesn’t void your warranty - I just RMAd my pixel 8 after it developed the pink stripe syndrome.

I’ve used graphene for over a year, and it’s been solid. If you have the sandboxed Google play installed all apps will work fine, and as long as you don’t rely on heavily commercialized apps everything will likely work without play services as well (sans push notifications for apps that rely on firebase). RCS will work if you have Gplay services and the carrier services app installed.

One in a while there will be a slight hiccup in the UI, but I’ve experienced far worse on stock android, so I’m assuming it’s normal operating stutters. All in all it’s very reliable.

I’ve been transitioning over the last week or so, on a new 8 pro,which is the same dimensions as the 4.5 year old Samsung it replaced.

So far, I have two banking apps from the same UK provider that don’t work due to them checking the same flags as Google Pay (12 other banking apps I have work fine), one parking payment app that doesn’t work and I’ve been told uber has started to be glitchy with their latest update.

The work around for all of those (apart from Google Pay) is use them via the web browser where they are fine.

Pixel 8 devices are the only recommended devices that have “minimum 7 years support and hardware memory tagging support”. I’d personally go with an 8 Pro. The GrapheneOS Usage guide can answer most remaining questions.