I'd like to go Linux dual-boot at some point, but what's the best flavour for gaming, and how does nVidia perform in Linux?
I'd recommend Linux Mint to start with, its based on Ubuntu which all the developers test against as its also the foundation for SteamOS. The UI is very similar to Windows and easy to use, I much prefer it to the Unity UI in Ubuntu.
Game support is rapidly improving, a few years ago there were just a handful of Linux games in steam now there are thousands. Just over 50% of my steam library has Linux versions so I have plenty of games to play
I've found the nVidia graphics drivers to be stable and not had any issues. One pretty big issue with Linux gaming is that almost all the games use OpenGL which is not as efficient as DirectX, so your FPS on Linux will almost certainly be lower than Windows. If you have a decent graphics card that can maintain a high enough FPS its not really an issue. Hopefully Vulkan will catch on with devs and then it should be a level playing field with better performance than DX11 and similar to DX12.