[chaltun]

http://www.travelnotes.cc/cozumel/links/todoreviews/chankanaab.html

above site covers reviews of the park by various visitors. Interesting. Do a search on Chankanaab for more info.

In my opinion, since it has more for me to see/do, and it's a really full day experience, I say Xcaret. I've been to both but like Xcaret better.