Actually this was our second scheduled port - were supposed to stop at the Private Island, but it was the week after Hurricane Sandy & some damage occurred there.
We didn't go on any excursions at St. Maarten. I went off the ship to the dock-side shopping stores. Bought a CD from the Steel Band playing there.
Enjoyed the ferry ride across to St. John, the bus driver was personable and interesting narrative. Amazing views of the beaches & ocean from the high hills. I gave the tour a 3 because we were supposed to have time for shopping at the end, and since there are a lot of little boutiques and independent jewelry stores, I really wanted to do this. He spent so much time at a little rest stop getting refreshments that we only had 15" before the ferry left to go back. At St. Maarten there were golf carts making round trips from the ship gangplank to the end of the pier. Great for folks who have a hard time walking a distance. None of them at St. Thomas. The tours don't take this walk into consideration when rating the tours as "easy".
We had not been to Grand Turk before, so the tour was all new ground for us. We did the "Trolley Train", and again, the guide was very knowledgeable about the history of the island, enjoyed his narrative. The problem with the train was that it has seats that face each other with maybe 18" between them so we had a very hard time being comfortable with the other passengers across from us. Again, no golf carts to take passengers from the gangway to the end of the pier.