Cancun was the biggest disappointment...not only the commercial aspect but they had a red flag out the entire time we were there indicating it wasn't safe to go into the water...albeit I wouldn't have gone in anyway as it just looked dirty to me. The clear, aqua-colored water in Jamaica spoiled us, methinks.
I hardly spent any time in Cayman. We always had a direct flight from Atlanta to Montego Bay but for whatever reason, on one occasion our plane touched down there for about an hour or so...just enough for me to have to answer yes at an IRA audit when asked if I had ever been there. Talk about a red flag! LOLOLOL (it really wasn't funny ;)