I really don't know enough about CCRs yet to give you any insight on this one... I am still a newbie diver in general, so tech diving is a little while away for me yet... I like the idea of CCRs because of the hours & hours of gas available without using stages & that you can change your gas mix as needed during the dive, again without stages. I am quite sure, with the tiny bottles on a CCR, that you would still need stages for the higher O2 stops in accelerated deco, but being able to go through the first few stops with just the CCR is awesome... If you don't get a spot in this presentation, I will try & ask the question for you about going from OC to CC & see what he says...