I spent a couple of night at Mary's and I was impressed by the great view of the Ocean on Simpson Bay.
The beach bar is really nice (live music and cold beer is all I needed). Wifi coverage almost everywere.
The bad surprise was the room. Not clean as I would expect for a 300$ room and the internal garden was very dirty. Early in the morning the planes from the 100-ft-far-runaway started to land and take off. That wasn't a problem for me since I was awake very early in the morning because the jet lag but I guess that if you want to fully enjoy the Carribbean with some rest that would be impossible.