If you have more than one device you want to integrate into a VR space, having them within nanoseconds of each other means the lag/spatial difference will be mu

If you have more than one device you want to integrate into a VR space, having them within nanoseconds of each other means the lag/spatial difference will be much better. The closer and more stable in time, the better. Currently most consumer VR gear is limited to a set of devices run through a single machine.