Guam is where I got certified for basic and then advanced open water. I lived there three years and found the diving to be spectacular. I moved to California, sold all my diving gear at a yard sale, and then was sent to GITMO for three months. Not as a prisoner :) I was there in the 90's when Cuban and Haitian refugees were housed there. Lucky me, the base exchange had a Christmas sale on dive gear, so I was able to dive and snorkel there. More turtles and fewer sharks than Guam. Both places were nice. Haven't been diving since :(