Cozumel Diving
My favorite things about Cozumel are the affordability and ease of getting there. From the United States, it's a quick single-connection or even direct flight and that means all in 1/2 a day, you can leave your house, hop a flight, and be IN THE WATER by 1PM: depending how far you have to travel. It won't cost you an arm and a leg, either! :)
There are at least a dozen reputable dive operators to choose from on this small island - probably more. Dive & Stay packages are quite popular, and can run anywhere form $350 to $1500 (USD) depending on the duration, location, and resort options selected. I personally took an eight day trip that included 7 days lodging, two meals per day, and five two tank boat dives with unlimited shore diving for about $800 USD...the eighth day I went solely on the local economy for about $60 USD. I'd rate the five, two-tank dive days about an average expectation for a dive trip in Cozumel but you can be as frugal or as liberal as you like. For the REALLY budget-conscious diver, there are a handful of cheap hotels in San Miguel that can be had for under $40USD per night if you want to try booking dives a-la-carte for less than what the resorts charge on their packages. There's a MEGA (grocery store) on the southern edge of the city for all of your grocery needs, or you can dine at one of many restaurants near the town square and along the main coastal passage way. I, personally, chose to mix my trip up and found it to be a little less money, but more stressful to do the a-la-carte-thing. However, if you want a REAL feel for the local atmosphere, I'd say that's how to do it.
The diving is good to great, with rather consistent visibility from 80' to 100'+, and water temps in the low to mid 80's (Farhenheit). However, that great visibility comes at a cost in current. Strong gulf-stream currents sweep past the island at all times of the year, so drift diving is the norm. (Also, the most enjoyable given the conditions) Many of the reefs offer some releif from the flow, but not much and you can plan on drifting at least a little from wherever you put in. The structure consists of some patch reef, spur-and-groove, and wall formations. (The walls being my personal favorite) Marine life will not disappoint! While there I saw zillions of little macro critters all the way up to nurse sharks, turtles, and spotted eagle rays. Very cool to see a mix of big and small animals. Oh, and did I mention the brilliant cobalt and turquoise appearance of the water that just SCREAMS dive paradise? :)
The currency is the Mexican peso, but US dollars are widely accepted. I found street prices to be somewhat less negotiable on Cozumel, as opposed to other hot tourism areas like Cabo San Lucas and Cancun. Dive prices were not negotiable at all with many of the dive operators I spoke to. (Y yo hablo espanol, compadres!) Oh well - The rates are still quite fair and you'll enjoy your time underwater in Cozumel.
Topside, the city of San Miguel sort of ebbs and flows with the cruise liner schedules. Boat comes to port: Town bustles. Boat leaves port: Town goes to sleep. I was surprised to find popular tourist clubs (Sr. Frogs, Margaritaville) empty or even closed after 5 or 6 PM on some days. That said, get out and explore like a local - Just be careful of solicitors: They're around and sometimes may try to sell you some things that can get you into trouble, depending which street you walk down. (I'd stick to the square and main roads if I wasn't with somebody local who could vouch for my interests) The square is a nice area to kick back and enjoy a little food and if you're lucky: Live entertainment via fire dancers, bands, mariachi, or other street performers. Cold beers can be had for $2-$3USD, or about 20-30 pesos.
Getting to and from the airport is relatively easy by taxi, and many resorts offer shuttle service. Also, there's a ferry that runs at least twice daily to/from Playa del Carmen if you feel like checking out what it has to offer (Mayan ruins, and Cenote dives are accessible from Playa). It takes about 45 minutes and will cost you from $10-$20USD each way.
I've already stated that flights to Cozumel are easy to come by from the US. Now, being the popular cruise stopover that it is, if you find yourself landing for a brief stay in Cozumel via cruise itinerary - It's probably an outstanding value as a port of call that offers great diving. :)
Enjoy!