Snorkel or dive or do a mix; I wish I'd done an introductory dive to get myself started!
They say you get what you pay for -- each dive outfit has their own moorings and licenses to stop at different parts of the reef. We loved the Silverswift but don't have much of a comparison.
Hike the trails (~2 hrs for everything) and take in the scenery/wildlife. You *can* go swimming but please heed the posted warnings / conditions.
