Since the last update I have been fortunate to visit four further sites, including Cayo Levantado in the Dom Rep, Roatan in Honduras, Seychelles (again) and most recently The Sea of Cortez. All have something worth seeing, the later being the most unusual, with plenty of differences from (my experience of) typical tropical environments. Cayo Levantado was a little dissapointing due to the level of exposure to the prevailing winds from the Atlantic. Roatan provides ideal safe and varied snorkelling, although very popular, so lots of people, all the time. Seychelles always interesting, with plenty of Acropora coral, but continuing signs of distress.