We have stayed there a few times. It's one of our favorites. The beach (Bloody Bay) is beautiful. The nude beach does get some walk by, but in the late afternoon evening it's pretty quiet, and we loved watching the sunset from the large hot tub on the nude section.
We didn't snorkel from the beach, but they used to take people snorkeling in a boat from the watersports cabana. Couples Negril is a great place.