I got TOASTED at Princess Cays. Even wearing the super SPF 60 sunblock, make sure you re-apply it often, and PLEASE DEAR GOD pack some After-Burn with Lidocane because for some stupid reason, they do not have that on board in the shops. I rented their snorkel equipment and had a great time in the water, but our last cruise we bought snorkel equipment of our own and packed it with us. It was cheaper than renting, and I didn't feel weird about putting something in my mouth that thousands of other people had already used. Oh, yes, and get an underwater camera for each kid - CVS has them around here - much cheaper than buying on board - your kids will love it!