we did it once and will not do it again, your time is so limited with the excursion. You can do it easily and cheaper on your own. All you need to do it budget your time, you grab a cab at the pier, go to Red Hook Harbor, the ferry for Cruz Bay leaves every hour on the hour- so plan your cab ride from Havensight accordingly-its about a 20-30 minute cab ride. Once you dock at Cruz Bay, walk the pier, grab a cab to one of the many beaches. Trunk Bay is gorgeous but it can get very crowded. go to www.vinow.com
for beach and ferry information.