Shark Ray alley is quite different than Sting Ray City. I liked being able to dive and sit on the bottom at Sting Ray City. Shark Ray is much shallower so you have to snorkle. Hol Chan is a good dive. We usually do it the first day because it is shallow just to check out our gear and get used to diving again. It is close to Shark Ray alley so you can do both at the same trip if you want.