I've recently switched to KDE with a Nvidia card, and haven't had too many issues. I did have to mess with the vsync settings to get rid of some screen tearing

I've recently switched to KDE with a Nvidia card, and haven't had too many issues. I did have to mess with the vsync settings to get rid of some screen tearing in fullscreen apps, but I've had the same issue on Windows 10 in the past. The fractional scaling worked great for me out of the box and was the main reason I made the switch.