Baseline (Widescreen) Solution & Issues
Native. Select your res in the pause menu.
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
Eyefinity / Surround Specific Solution & Issues
It works in surround, there's no FOV errors. But the hud and everything else stretches.
The "Keep Aspect Ratio" Options only gives you resolutions that have the same aspect as your "Recommended Resolution" in windows.
4k UHD Specific Solution & Issues