I was recently at a Microsoft Training Centre, where we also had a chance to test the Hololens. All in all, it's crap. It is pretty heavy, so I can't imagine wearing it for more than 10 min. The latency was ok, but still somewhat disturbing. The gesture recognition was bad. I, and later on also the Microsoft guy, had to tap twice several times to trigger an action. The shown floor shop example was a bad choice. Speed at the shop floor is key, for workers and for other functions, and this is what the Hololens didn't have. During the show off they had to restart the Hololens - a clear fail I would say, but judge for yourself.
I was wearing it for multiple hours straight without any fatigue. You need to tighten it and use the right nosepiece, having it rest on your forehead rather than your nose.
Gesture recognition was really good when I was testing it, it really doesn't take long to learn. Rarely would I have to tap twice. The standard gesture is bringing your index finger and thumb together, I definitely had a hard time explaining that to users.
