I was just there, stayed at Barcelo Maya Palace where Dressel Divers is based. We didn't expect much but were very surprised not only with the dives but the quality of the dive operation. The entire staff is imported from Spain and the US. Decent boats, three dives per day, couple sites with swim-throughs and wrecks, huge bait balls of fish, lots of life. For your last dive, the in-land Cenotes (freshwater blue holes) are a must (last because it's a great freshwater gear rinse). My wife with about 50 dives was a little nervous but agreed it was no big deal in the end.