My (personal) answer is that, when I first visited Cozumel, I went with Jeremy from Living Underwater and since I was far from disappointed have stayed with him ever since out of both loyalty and customer satisfaction. I have no doubt that, for what I seek in a dive op, I would be just as well served by Aldora, Blue XT Sea and several other "boutique" dive operations but have no compelling reason to change. At the same time I recognize that each diver has unique needs and desires in what they seek and it is fortunate that Cozumel has so much healthy competition and variety. I don't think there is any "one size fits all" dive op because each of us has different criteria....whether it is price, tank size/type, surface interval location, dive sites, freshly baked cookies or some combination of the above.
What I value about ScubaBoard is the whole range of freely expressed opinions and reviews (hopefully without flaming) and the contributions of people like Dave and Christi who offer up advice, island information and a wealth of other knowledge without overtly using this forum as a place to troll for business. Yes, that they are posting here likely is beneficial to their business but any dive operator is equally free to post and it would be nice if more of them did.
A somewhat perverse dilemma in posting recommendations is that we do it for several reasons. We want to share our experiences and we also want to send business to our favorite dive op because we want them to succeed but not so much that they won't have room on the boat for us!