>>350412543
I wouldn't use it to scale up to 100%, setting it at 1.2 to supersample or just at 1 to add the sharpening pass helps though. You can use reshade to add sharpening in most games for the same effect as setting FSR at 1 at this point. 

>>350412792
Go to WMR for SteamVR in Steam, go to the gear icon, properties, beta, and in the drop down select the beta. According to Microsoft and Valve the drivers were really inefficient beforehand in that they would make an extra copy of the framebuffer which wasted a lot of VRAM. With the "Direct mode" beta that overhead is eliminated and WMR headsets perform as if they were native SteamVR headsets. I've found the boost to be very useful for keeping resolutions high, especially in Skyrim with all of the HD texture packs I use.