Scuba Club Cozumel
Scuba Club is that rare thing that does exactly what it says it will do: gives you a great diving holiday. This Cozumel dive resort is not fancy- but it's also not expensive.
The accommodation is simple and plain- but very comfortable, with plenty of space, good hot showers, and a place for hanging things to dry.
The food is also simple and plain, but tasty and ample (the daily specials are highly recommended, as are the beef tacos). Note that at the moment they only serve breakfast and lunch- you can order dinner but really there are so many good places just down the way that it's more fun (& better/more interesting food) to go out. Drinks are reasonably priced and very good.
The location of the Club is great: just past the main drag, so it is easy to get to an amazing array of really good restaurants / ferry / etc., but it feels peaceful and separate from the hard core madness of the strip. The resort itself is organized so that everything is right there: food, dive shop, boat, water...
The staff are friendly and helpful (if sometimes a little persistent about making sure that the billing is being done correctly- but I would rather that they were a little over careful than have to sort out billing mistakes at the end). They get to know you and your preferences really quickly.
And then there's the diving in Cozumel, which is the main point of the exercise. Having all the shore diving you want is super. We were a group of 8, and had the same boat, crew and DiveMaster for almost every outing, which is brilliant. We chose Cozumel because we had 2 brand-new divers in the group, a bunch of intermediates and a couple of experts. Everybody enjoyed the dive outings. The drift diving is great and the wreck dive was fun for everybody. We saw the biggest seahorse any of us had ever seen, several Splendid Toadfish, and all the usual suspects (turtles, barracuda, moray, some *huge* spotted eagle rays, several varieties of puffers, etc).
On a practical note, if you are renting a regulator you are issued a numbered one at the beginning of your stay and you keep it (& the BCD if renting) for the duration. Also, bring a padlock & a flashlight!
