Key Largo is excellent for getting your certification dives in. My wife and I live in Lafayette, LA and the LDS here does their certification dives in Destin, FL. It's the closest place to Lafayette with decently warm water and visability. But we checked the averages (for last June in our case) and both the water temps and viz were head and shoulders above Destin. So, we just combined our summer vacation with our certification dives. Loved it. Besides the warm water and viz in Key Largo, the shallow reefs are wonderful, don't have to worry about strong currents, etc. The only other place you could feel safer is in the pool. In fact, we went back to get our AOW certification there. Going back in June for 10 days of diving, of course all our vacations now are dive vacations. We Love The Keys!