In Grand Cayman we went with
Snorkelers Dream Catamaran to stingray city and it was incredible. There is nothing like sailing on a catamaran except going to Stingray city on a Catamaran

We did 3 snorkeling stops with stingray city and we sailed back while the Captain played guitar, it was an excellent day! The water was crystal and the crew was wonderful. Burt was the first mate and he was so sweet and friendly. The price was great too, $34 for us adults and only $20 for the kids.
The catamaran is really nice, loads of room to stretch out and relax, we only had maybe 15 people including us on board and (we are 6) and it is a really big cat...50ft(?)