This was a NEW experience for us, so uncomfortable to start; it takes a bit to get used to breathing through a regulator. But, outside of truly scuba diving, I can't imagine that you'd otherwise have an opportunity to see and experience the reef the way we did. You're down @20 feet, swimming and exploring right along the reef. It was nice for the guide to take pictures (at a cost afterwards of coarse) so that you could concentrate on the experience. Swim time was 30-45min and the same in boat travel time each way. If you get sea sick, pre-medicate.
We would definitely do it again and probably would rate it higher with more exposure (and therefore comfort) with it.
Our guide was CJ...very informative and patient especially with my special needs son. MUCH APPRECIATED!