We loved Chankanaab! (family of four with 2 teen boys) We felt the admission price was worth it, especially since we spent our day there, not just 1-2 hours ($12 pp when we went). The place is beautiful. Great snorkeling because it has a rocky, not sandy entrance to the water.....there are rock stairs to enter. There are no vendors on the beach to bother you. Lay down chairs and palapas are scattered throughout the beach area and free of charge. If you're hanging out close to the restaurant, a waiter will come out to serve you, if you want, but not bother you if you don't want to order anything. The nature walk through the mayan replicas was interesting and made for some nice pictures. There's a very small mini-golf course that you can play on for a couple of bucks. Lots of iquanas walking around. There's a few shops with pretty good prices and no pressure to buy. The bathrooms are very clean. It was a really nice, relaxing way to spend our day in Cozumel.