Shuttle or Car Rental

Hi Everyone:) We are looking to do one of the snorkel trips to Buck Island and are trying to decide between half day or full day and whether to use a shuttle or rent a car. If we did full day, we'd most likely just shuttle at $32 RT for the two of us.

BUT....a rental car is $45/day. If we decided to do just half day snorkel trip in the am, would this be our best bet? Is there parking near the pier where the tour companies go from? Is it worth having a car for the second part of the day in Christiansted or is everything walking distance anyways? Without going back to research for the sake of this one thread, I have three things noted to see while on St. Croix ~ the rainforest, Domino Club/beer drinking pigs, and RumRunners for lunch/drinks. So, are these three things walking distance or would they require a car?

TIA. Appreciate your help. Brenda