We dove Bermuda first time August 2009. We dove Blue Water divers two days. We picked them bc they were closest. The first day I thought the Capt. was less than impressive. Different crew the second day and they were great. I have heard good things about Triangle Divers. I have not heard anything bad about Dive Bermuda, the op at the your resort. Based upon location alone I think you would dive the op at your resort unless you learn of a good reason not to. We were told nitrox was unavailable and probably not necessary based upon likely profiles. We dove the Hermes which was nice and the M. Celestia which we loved, not so much of the wreck, which is scattered and not much left other than the paddle wheel which by itself was pretty neat, we liked the reef structure and terrain and found some nice swim throughs/tunnels. SW Breakers was our shallow dive which has a nice swim thru. As far as water temps check out Blue Waters website and they have a link to a table of average water temps by month. We had good lunches at the Swizzle in, avoiding the prime time of noon and crowds. and had at a great dinner at the Reefs, both nearby. Check out the bus and ferry routes and schedules, a great way to get around the island.