My wife and I have stayed in several places in St Thomas (including resorts), and we both agree that this was by far our favorite.
It's located on the "other side" of the island, quieter and more peaceful. It's quite a ways up the mountain and might be a bit difficult to find at first (search for the dancing orchid on Google maps). A car is a must, and you will be wise to get a Jeep, though we made it in a small sedan (it made the driver lots harder).
The view from the mountains is incredible. We were lucky and were the only guests, so we had the whole floor to ourselves. Our room was very spacious (with plenty of storage) with a beautiful four-poster bed and direct access to a large porch (shared with the second room). The Spanish architecture really made it stand out.
Mary was a wonderful hostess. She kept a really clean house and was helpful throughout our stay.
Overall, if you don't mind not being on the tourist side of the island (though it's not a long drive away by any means) and enjoy beautiful views, Mary's place is by far the best bang for your buck! We highly recommend it.