Actually Martin, sorry to say that there have been 2 fatalites while diving the Prism, one was a friend of mine. But both appear to have been medical issues. Equipment was recovered and working properly.

And as for the habits of the users, most that I know are tmix certed and doing plenty of deep stuff. There are plenty doing deep stuff, including a team of working divers who regularly do dives in the 600 ft zone...