While playing Arma 3 with the Rift, the Letterbox modi give me the best setting, but those black bars are blocking too much of the upper and lower borders. I think an option to adjust them or to disable them, will be a solution.
Nevermind my first post, i got it wrong.
I corrected the FOV in Arma to fovTop=0.89999998 fovLeft=1.1 and in VorpX i use Simple Aspect Ratio, everything is fine now. The one and only thing i’m looking forward to, is Arma 3 in Geometric 3D. I hope that will be possible, because Z-Buffer 3D isn’t that immersive, especially in cockpit perspective. For comparison, check the cockpit of the truck in Outerra:Anteworld, best 3D-effect i’ve seen so far.