We used Stingray City Charters & got a great internet rate - seemed like it was about half price of the others -- and were very happy. Went to Stingray City & 2 other stops. There were about 15 on our boat, not too crowded, & we had a great time. The extras we got were fresh water, soda & a fresh water shower. Someone was there to take digital pictures of us at Stingray City & we could see them on the way back. Of course, they were good & we ordered a couple. The CD came in about 2 weeks & we were able to print them out fine.
Stingray City Charters picked us up right across from Cap't Marvins. Heard great things about them & Cap't Brian, too. But we really liked ours, not crowded & seemed much less expensive & no trouble doing it over the internet.
Next time I would be interested in trying a catamaran. There was a huge one docked right about where we took off (actually I think they said it was a "trimaron") & looked like it would be a lot of fun.
Have a great time.