I dove in Cozumel with DWM after my fourth dive.
They were pretty good. DWM took us to a beginner site to assess our ability, Palancar and Paraiso. We dropped down off the boat onto a sandy area where we could sit on the bottom, collect ourselves, adjust our BC's/buoyancy and then as a group we started going through the reef.
If you feel that your buoyancy is not stable and you are not "floating", remember to add a bit of air to your BC once you get to depth and make sure to stay off the reef. Maybe at least 6 feet off the reef if you feel that your buoyancy is not stable or you keep sinking. For beginners, its a good idea to stay a bit shallower than your DM and group, your air will last longer that way.
The good thing about DWM is that they have multiple boats and will divide groups by experience/ability. On the first dive I saw a newbie (a really nice guy) with a camera trampling the reef. The next day, he went on a different boat while we went to faster current sites Barracuda and San Juan.
On this trip, my brother is just starting to dive, so we'll be diving shallow sites on most of our dives. There's more marine life to see, more colors and warmer water.
No matter who you choose, I'm sure you'll have a great time.
-nt
