Just wanted to let you know that we did this last week and it was AMAZING!!
You arrive and they take you into the jungle on this bug Unimog truck and tell you all about the history of hte area, we saw mayan in traditional outfits too. The zipline is like nothing I've ever seen, you don't climb up your are hooked in a slowely lifed automatically all the way up on the tower. They crew working there was incredible, very professional and they said that its only been reopened for a short time since the hurricane etc.
The zip line runs are incredible, watch for the macaws you can hear them and sometimes see them:-) WOW!!!