We have not been, but I did alot of research on Cozumel beaches, so I will tell you why we picked this one (already booked it by the way!!!)
Reason 1 -- no crowds
They only take reservations, which means that they have a limit of people that they allow in, so it is never crowded according to everyone that I have spoken with. They are also about a 15 minute drive from the port, and most people don't want to go that far. I don't know if you have noticed, but it is not that well-know (yet). All of these factors should contribute to having a less-crowded environment.
Reason 2 -- Largest pool of any beach club
We beach people, but we love to have the option of hopping in the pool when the salt and sand get tiresome. Not many clubs even have pools, and those that do have very very small ones (Check out Mr. Sanchos pool ---teenie tiny). This pool is large, and it has a swim-up bar which is very nice.
Reason 3 -- Economics
There is a set price that covers everything -- food, drinks, water toys, etc. This is great for me, because I won't have any surprises when the credit card bill comes.
I am slightly obsessive about our trip planning, so I really compared all of the beaches, and this is what I came up with. I hope it helps.
