I stayed at the Viva Maya when I was there. They have a dive shop right on site. I dove with them the first two days, doing a boat dive and diving the cenotes, and had a really great time. They were super nice. I came down with a miserable cold 3 days into the trip, and had to cancel the rest of my planned dives. There was a no refund policy and they weren’t allowed to give me a cash refund for the dives I missed, but they did give me merchandise of comparative value, which I thought was really nice of them since I wasn’t expecting to get anything.
I only went the one time, so I don’t have anything (negative or positive) to say about any of the other hotels or dive operators.