I've stayed at all three San Francisco hotels and without a doubt I would choose to stay at the Stanford Court. The rooms in the hotel are a lot nicer than either the Parc 55 or the Downtown Marriott. The tooms at the Stanford Court have a European feel with beasutiful white comforters on the beds and the bathrooms are a nice size. At teh Downtown Marriott I had a decent size room but it had the standard decor of a hotel room (huge flower print linens on the bed) and the rooms at the Parc 55 were a bit shabby and I was Platinum when I stayed at both hotels. But given a preference without a doubt go with the Stanford Court. The only drawback is the location (it's located at the top of nob hill so its a hilly way to get there if the cable cars are full)