I have dived with Hidden Worlds DMs in Dos Ojos and Bat Cave several times, they're DMs are top notch. I would not think of diving Dos Ojos with any other dive op and you can't beat the fun of the ride out to Dos Ojos on their open flatbed trucks either. I have also dived Heaven's Gate with them which is incredible, but at the time my Wife and I did it, they required that you had at least 4 or 5 Cenote dives under your belt if I recall right, but they had only just opened it to divers. One thing, if you do Heaven's Gate, its quite a distance thru the jungle to get there and will take a good part of a day to do. Heavens Gate and Dos Ojos are my favorite Cenote dives.