We booked the 4 hour tour and we excited to spend the morning on the water. Our guide, John Hess, was excellent from the beginning. His "not so brief" briefing was informative and well rehearsed. It was obvious he had groups in the past that were problematic, so his briefing was designed to head off problems before they started. He was engaging and answered all questions by the group of six. Once in the water, he was encouraging and complimentary. He even offered to take photos with one of the couple's camera (for them). He took us to a couple of sites to snorkel and both were filled with plenty to see. He dove down and took lots of pics and pointed out the sea life for all of us. He made the trip a success. On the way back, it was obvious the weather was getting rougher and the ocean was not easy to navigate. He suggested we cut the tour short and we agreed. He offered to give us the difference between the 3 and 4 hour tour back as a refund. We simply offered to give him the difference as a tip. We did not see the other two couples offer up a tip after the trip, but I hope they did. In general, these tour guides live on the tips, so please consider this when booking.