We chose On Bird due to their focus on safety, their provision of child-sized equipment, and the fact that they would have a guide in the water with us. All factors exceeded expectations, and we had a fantastic experience from start to finish.
Pick-up was prompt, and our guide - John - gave us the rundown on what to expect and all safety guidelines. Our group was 4 adults (2 of which were seniors) and one 8 year old, with only one of us professing to be a strong swimmer (and only one of us had ever snorkeled before). Safety continued to be the number one subject as we headed for the first stop to try on gear and get acclimated.
Gear for our daughter was perfectly sized - she was very comfortable with her mask, snorkel, fins, and life jacket. All gear was well maintained and comfortable (they had asked for sizes beforehand, so it was the right size for everyone).
John was amazing - friendly and knowledgeable from the start, and very patient with our newbie group. At one point, he was pulling part of our group through the water while they hung onto a buoy. And, he "showed off" and performed some tricks underwater to the delight of our daughter.
I have never been snorkeling, so I can't compare the reefs here to other places. I'm sure there are much better examples in the world, but I was absolutely transported. It was beautiful, and amazing, and I definitely will do more based on this experience. I can only hope other tour operators perform on the same level as On Bird!