Assuming this won't be your last snorkling trip, go ahead and invest in your own. It'll pay for itself pretty quickly. Concur with other posters on the vest RCI requirement at Coco Cay. Comes in handy actually as although the snorkling area is swimable from shore, it's several strokes out. Was underwhelmed by the views. More grassy areas than coral which is what you need for really great scenery. Likely the reason why RCI sunk a piece of a ship and an airplane out there--to create an artificial reef. Even at that, not much to see. Also, the jellyfish were out in full force (September), but they're a part of the scene as much as other species. They're difficult to spot, and I spent more time watching out for them than looking at what little scenry there was. Got a slight sting anyway. In fairness, it could be I'm being too harsh a critic have seen spectacular underwater sights in Hawaii and the US Virgin Islands. Speaking of which, unless you're on an official excursion, no vest requirement at USVI sites. You mention Trunk Bay on St. John--excellent snorkling; and Megan's Bay St. Thomas--wouldn't bother for snorkling. On St. Thomas I'd recommend either Coki Beach--good near shore snorkling, but very crowded and touristy; or Sapphire Beach Resort--short swim off shore to really neat coral formations and tons 'o fish. I do tend to drone on--sorry!
