I just stumbled on this thread. I've been diving with Roberta's Dive-Eco Cozumel for a few years, at least 75 dives, and have always had an excellent experience with this dive op. As her op has grown since they bought blue bubble, the range of clientele has widened, from mostly repeat customers with known diving experience and abilities to people like the original poster on this thread; referrals who come in from another dive op with an unknown history. If there was an error in judgement here by the dive op, it was the captain who allowed the evidently inexperienced diver to try descending again after initially failing. Bet he won't make that mistake again!
Once again, I can attest to the quality of this dive op from extensive personal experience. Oh, and they're hardly a "cattle boat" operation; they have a few small "6-pack" boats and had one larger boat (still not the cattle boat size) which was severely damaged by Wilma.
Now, as to the quality of "open water", all I can say is that I tried to rent it once. As I was checking it out, the blockbuster employee looked at me and said, "Dude, this is the worst movie I've ever seen, and I've seen alot" Soooo.....I put it back and got something else.