We did, and plan to do again, Cozumel H20. Personal service, amazing snorkeling. Just don't look down into the boat at the fish guide while motoring to your spot, like I did, as she shows you the different species. It made me seasick. The kids loved it. Oh, and use the absolute strongest sunblock, sun shirts you can. We did and were fine, but the other family we were with didn't and it almost ruined their cruise.