With the 1080 (I know that’s not what you asked) I use the VR preset and 2.0 pixel density. I then upped the terrain textures to HIGH and adjust trees and grass up a bit. Runs very smoothly.
You also didn’t ask but in IL2: BoS I use the debug too in the Oculus SDK to up the pixel density to 1.7 since BoS doesn’t have it’s own density slider. I use the Balanced preset and a low screen resolution per their recommendation. I find that IL2 runs liquid smooth compares favorably to DCS; but not in VR. It runs ok but “tears” a bit in multiplayer, especially the right eye. I love it though. Great exercise constantly checking six against players who can see and recognize you much farther away.