Same setup here. Multiple displays don't work well for me. One of the displays doesn't often get detected after resuming screen saver.

I have two monitors connected to the 3070 and it works well. The only issue I had was suspending, the GPU would "fall of the bus" and not get its power back when the PC woke up. I had to add the kernel line "pcie_aspm=off" to prevent the GPU from falling asleep.

So... not perfect, but it works.

Huh. I’m using 2 monitors connected to a 4090 on Linux mint - which is still using X11. It works flawlessly, including DPI scaling. Wake from sleep is fine too.

I haven’t tried wayland yet. Sounds like it might be time soon given other comments in this thread.