That is pretty sweet. That guy has too much time on his hands. What i would have done is take something like those video glasses and wired them into the gun. Meaning u dont have that huge bulky screen on instead u just put some goggles on and ur ready to go. I confess i didn't finish the vid. How does the guy move around?
By actually moving around. Think he also pushes a button that disables it so that he can go back to the middle of the room so he can start again from his current position.
So in order to finish an entire Fear2 Level you gonna need an aircraft hangar lol. That would be cool.