The reason I only dive in warmer water is that I do not have to use a wetsuit as long as the water is above the 70 degree range. In my opinion wet suits are overrated. Now if I dove every day I would absolutly invest in a wetsuit. But I must admit everywhere I go diving the people who work in the dive industry (i.e. on the boat or in the shop) can not believe I dive without a wetsuit.
The diving around here is very different than any of the warm water destinations because the visibility around here underwater is usually less than 5 feet and the temperature is well below the 70 degree level. As aresult you have to wear wetsuits (or even drysuits) to be able to handle the exposure to the cooler water.
As far as equipment I do not know if different equipment is needed here because of the water temperature differences (as long as you are not diving in the wintertime and yes there are people who dive in the quarries around here in the wintertime). Another advantage of diving in warm water locals only need one type of equipment. I try not to be an equipment hog because all my gear has to fit into one bag for travel purposes. I bought my own equipment about two years into diving (and to let you know it will never pay for itself money wise but it is your life support system once you are underwater) and I have the Regulator (Primary and Secondary), Octopus (guages/computer), BCD, Mask, Fins, Snorkel, Dive Booties, and a light. I bought the digital camera and housing more recently because I did not want to keep borrowing gear to support my underwater photography addiction. The main reason for buying your own equipment is familarity and comfort. For the most part it is far more economical to rent the gear if you are only diving a few times a year.
Pat Hanauma Bay is AWESOME!!! It is worth the price of admission. I have to admit that I wanted to snorkel all day long in Hanauma Bay when I was on Oahu. I had to come ashore when the leg cramps set in after about four hours. Awesome place went there three times during the week while on Oahu and it is probably the best snorkeling in Hawaii and the investment (one dolar) in the tram ride back up the hill is the best money spent on any vacation (think priceless)!
