As a matter of fact, I have shot it from depth, about 60 feet. I carry a 120 ft reel with me when we drift dive in Cozumel just for that purpose. It worked well using an octo to fill from the flapper valve, and the over-pressure valve did its job ok. After watching me shoot it to the surface in Cozumel, the DM asked to buy it from me when we got on the boat. I sold it to him when we came back stateside, and ordered another one to replace it. We also wreck dive, so knowing that I can make my own ascent line if we don't make it back to the fixed line in time gives me better peace of mind. I'm always thinking safety no matter where or what I dive, and having this smb on me is a big safety "plus". I also like that its big for better visability in swells, and doubles as a horse collar on the surface should you need extra flotation. I'm surprised that the features this one has hasn't become standard for all the others out there.