Captain Nautica's Ultimate Snorkel Expedition was fabulous visiting 2 locations for an hour each. I saw at least 20 turtles and multiple rays and barracudas. Lots of fun. Remember to bring tip money which is not included but deserved.
After getting off the pier we were approached by multiple tour shuttle operators but all had to wait to fill their 12 person vans. We didn't wait. A bit further down the road a regular taxi approached us and for $20 a person they left and gave an island tour with just 6 folks. Nice. The island itself doesn't have much to offer except interesting vegetation. Save your money. Not a great island to explore.
$20 for an island tour on a large open air shuttle bus. Don't bother. They have tall/large hills overlooking a scenic harbor. A few photo opportunities to take pics; a few stops to buy drinks; and 30 minute stop at the beach/vendors. Total waste of time and money. Folks said that Virgin Gorda's snorkeling was nice.
We didn't take an island tour as the CCL ship itself warned of possible trouble on the island. We just walked a bit around town. The shopping area is a bit of a walk from the ship w/o transport for the handicapped. The prices were much higher than St. Thomas. Do your shopping there instead. Cleaner than St Thomas. Paradise Island Resort looked nice from a distance.