content: Yes it is designed so you can wear glasses underneath,  You could still see your hand in front of you when making gestures, the demo did not show you being able to pick up any objects, I'm pretty sure there is a demo out there where you can manipulate objects with your hands. For the 20 Minutes there was no issue with battery life, No idea what the maximum time you can use it for.  I personally would be very interested in buying one, if you are into buying cutting edge technology then you should consider it, honestly the FOV was not an issue after a while. Thanks for the interest :)