I have the Hero HD and love it for underwater, in water, cycling, stuck to light bar on truck for offroading or hwy driving, stuck to car with suction cup mount, in pools/waterpark, mounted to RC vehicle. Even video'd some of the grandaughters first moments of life - no not the delivery. I want to strap it to the dog but the wife won't let me. She says the dog is not my toy. I disagree, lol.........great camera, no issues with it.
It would be great for snorkeling either on chest mount facing down or hand held or with the wrist strap.