It is impossible to have a good display with a transparent lens, because you have to overlay the light that passes the lens with an even brighter light. Unless they find a way to dim shapes on the lenses, this will always be sub-optimal.

What will work is a camera on your VR device, that will give you a quasi-AR device, but those are still clunky and as you can see with the iGlasses they look a bit spooky from outside.