My daughter and I started going to Coz about 10 years ago, right after we got our cards. Our first trip we stayed at Hotel Coz and went with Dive Paradise, basically for the only reason that our dive instructor here in TN recommended them. 10 years and 150+ dives later, we're still staying at the same place and going primarily with the same operator. Their dive shop is right across the street from the hotel, which is a major convenience, and they have small fast boats for two-tankers in the morning, at a price that's just a few dollars more than the bigger cattle boats. Very little turnover in their staff and DM's (Matu, Giovanni, Hymie, all those other guys have been around since we started and they're all good). The only drawback is that their afternoon dives are very limited if you want just a one-tanker. You're on a big boat and you're going to one of two reefs right near the hotel, and that's it. So our last trip we decided to go with Aldora on a few twilight two-tank dives and we were impressed. It took us a while to get used to all that weight on our backs with the steel tanks, but the significantly increased dive times made it worth it. They're expensive though, much more so than Dive Paradise. We're headed back in January and we'll go with both of them again.