I have an Atmos AI -- just got it used on ebay and have 3 dives on it so far. I like it a lot -- the quick disconnect and compass are very nice to have. I selected it because of the user-changable battery, good reviews, ok software, and the AI means I don't need a separate SPG. (If the computer blows the dive is over anyway.) My only complaint is that it seems very, very sensitive to alarming on ascent -- the manual says it will alarm only after 4 seconds > 30fps, but it seems much more sensitive than that to me. Or maybe I'm just being a bad diver. (Being a used computer, I can see that the guy who had it before me had the same problem . . . alarms on every dive, even though the profiles looks pretty benign.)