I don't believe the motion sickness issue to be real. At least for people who don't have an unusual predisposition for it. Sure, the first week you can't use it for very long before feeling nauseous, but that naturally goes away with time if you stop using the device when you start feeling nauseous. Getting your VR legs is a real thing. Today I can totally imagine spending a whole afternoon playing in a DK2, as long as the game has proper support.
As for the distance to the screen, they are also much less bright than typical screens.