Snorkelling was great (Cozumel has the most beautiful blue water of anywhere on earth) and the excursion staff were wonderful EXCEPT they had woefully inadequate masks and snorkels. If we had taken our own it would be 5+ stars. Unfortunately they told us no need to bring anything and we regretted not taking our own masks.
Snorkeling and Dunn's River were absolutely awesome. I was leery because Dunn's River is supposed to be touristy and crowded but we were in a group of 15 and it was awesome. Snorkled remarkably close to shore and saw tons of fish.
Calm water, lovely "jungle" feel. Buffet at the barefoot beach was great with salmon/shrimp/scallop skewers. Barefoot beach never got crowded. Cabanas are great, cheaper (half the price!!) than Disney but no shower for the sand at the cabana itself like the Disney cabana (Disney cabana is expensive but much more luxurious).