Hi Mathew,
with all respect, anyone that would take seriously VR should consider Unreal instead of Unity, just simply because of the level of realism the engine provides compared to Unity, visual richness is one of the pilars to take on consideration for believable immersion, and that is where Unity cant compete.
We are a studio focused mainly in VR and we decided to go the Unreal path beacuse of its visual quality, got to say that missing oficial support for leap motion in Unreal is a pain in the a*s for the ue community, and there are lot of developers that would apreciate that, if you check on unreal forum, you will realize.
Greetings,
F.