Im pretty sure these guys will make quick work of sli problems with vr. Already there is a system that uses one gpu for each lens in vr. Of course devs have to implement it in the end. Also im really contemplating cancelling my vive order seeing as the games are so limited on that platform right now. Id probably just end up playing flight sims again.
There are already patches out to get Rift games working on Vive, including exclusives. The hack can be used for all current and future Rift titles, unless Oculus changes their development methodology to block it.
At this point in time, Vive's the pony to back, but I'm not spending several thousand dollars (thank you Australia tax!) on a decent gaming rig and VR headset just for mediocre tech demos, while Nvidia milks the public for all its worth with incremental upgrades instead of the generation-changing chips they already have up their sleeve.
4K on Ultra, SLI VR and a catalogue of AAA VR titles might win me back into the fold, but I think it's still a good 2-3 years away.
