I am in the same boat (no pun intended). Except I will have my open water certification done soon. I tried to get it done in Puerto Vallarta last month through the referral process and it was awful. The dive operators there were not reliable, did not show up as expected, and we only got one of the two days of diving in. Plus the water was very rough and not great visibility. So, hope your experience in Grand Cayman is much better that what I had in PV. However, I am also going to Grand Cayman and wish to use a reliable operator, and stay in a place (condo or villa) where they will come to pick me and my buddy up. I will check out Ocean Frontiers. Thank you for the info.