Hi, always nice to hear about VR with Unreal Engine!
edit: and I really loved the last Twitch about VR 
Thanks for all the info Nick!
@imille, there is not much official information regarding how to get the most performances out of UE4 on VR stereo mode, but there is at least a few threads about that on these forums. Did you look at UE-4-and-Oculus-Rift-Framerate-Optimization?
Cheers!