Just back from San Sebastian. Maria Cristina Hotel is a great Starwood property in an unbeatable location in this wonderful city.
Rooms are large and comfortable. They have some specially appointed "SPG rooms" (they have a specific mark in the door), but I think the main difference between these rooms and the others is probably just the view. I'm Gold and didn't get any other upgrade, but room was quite ok, with also a large marble bathroom (with two basins, separate bath/shower, and a door between toilette and the rest of the bathroom).
When we arrived, they couldn't find our reservation, but they managed it quite quickly. Very friendly staff and also very good breakfast buffet (including champagne, caviar and salmon).
If you go to San Sebastian, don't even ask for any other hotel (and if you go to the Northeast of Spain, don't even think of another city!).
We didn't try the hotel restaurant, because San Sebastian and sorroundings have some of the best restaurants in Spain (Arzak, Akelarre, Martin Berasategui, Elcano,....)