I think I'm the person Dave is referring to.
We took this tour. It was VERY interesting, especially if you like history and architecture. It was also NOT at all what I expected it to be based ont he description given...
The first stop was a viewing area with a WONDERFUL view of the bay that the ship is docked in and a great photo op. The tour driver gives a lot of history of the island.
You get off at Blue Beards castle, and are met by a second guide. You walk from the castle down to the Hagerson House, and tour that. If you love antiques, you'll love this part of the tour.
From this point you'll walk down into town and have plenty of time to shop. A couple hours if I recall. But, this is the best part--the ship is actually walking distance, or you can take a very inexpensive cab ride back to the pier rather than getting back on the same tour tram.
A few words of warning. This tour is NOT handicapped accessible...not at all. It is a WALKING tour. There are stairs,and quite a few of them. It is also NOT a good tour for younger kids, who will be very bored. There is no place to let them run around and blow off steam.
And, as you are approaching the Hagerson House, you will stop under some trees and be told about the local iguanas. Be VERY careful where you stand. The little devils are up in teh trees, and they poop and pee from up there, and you will be christened. YUCK!
Let me know if you have any other questions.
Anne