I’m on the standard LTS kernel (if I properly remember Debian defaults). I did check out the Linux Surface project before setting it up, though the standard kernal and Gnome config seems to work great out of the box. Even little things like the gyroscope and automatic brightness worked from the start, though it probably varies from model to model.
Edit: only thing that didn’t work out of the box is the camera. Going to tinker around with that at some point, not a super high priority personally but still nice to have.
A month or so ago I picked up an 8gb model and it’s been really nice, I wrote a blog post about it if you’re interested and have been really happy with it. 4gb is enough for note taking & code writing, web browsing, reading, and YouTube watching (at low/mid resolutions) and I actually got away with those on a 2gb RAM 16gb storage Chromebook + Debian for a while. Still though, if you can spring for 8gb of ram that will be helpful, and a necessity if you want to do things like run waydroid.
Gnome works great, just be sure to set up the on screen keyboard and run the custom hot corners plugin to make it work everywhere. Also, I know that chromium doesn’t have the best reputation in these parts, but you’ll probably need to use either a WebKit or chromium browser for their touch controls and PWAs.
I went with Debian, but I can’t imagine Fedora offering a much different experience. Mine worked fine without a surface specific kernel, but results may vary from device to device.
Last, I bought mine used for $99 US on EBay. Not sure how it varies from country to country but at least in the states you can find older surface models in decent condition starting at $70 US or $100 US for ones in like new condition with a keyboard & charger.
Edit: beyond Surfaces, if you’re deal hunting and don’t mind more research I believe most 2 in 1s running Windows or ChromeOS will accept a custom OS.