I just got back from Grand Cayman and did the stingray tour with Capt. Marvin's. We were so glad we booked with them after we saw the other charters that were sardine packed with people! The people were very friendly and informative and a person goes down with you to make a video of your exerience. Since there were only about 8 people on our charter we got to know them which made the video more fun to watch. Also, Capt Marvin offers an early tour at 8:30 and (9:30 ship time) so we had plenty of time to shop around after the tour. We had a blast and will book with them again in a heart beat! If you're still unsure, there will be people standing by the pier offering stingray city tours for really cheap, but you never know how crowded their charters will be or what type of service you'll receive. Oh and you get a free rum cake after and you just have to walk to Capt. Marvin's you don't need to waste your money on a taxi...it's that close.