Great place to stay!
While this hotel is quite large, and quite busy, once you are in your own room, you don't even realize just how big and bustling it is. My husband and I recently stayed there for 3 nights. There was a large conference going on at the hotel at that same time, which made it even more crowded. However, our room was beautiful, very quiet, and relaxing. The staff did a good job of keeping everything running smoothly during such a busy time. If you don't like big crowds, and prefer smaller, quainter hotels, do NOT stay here. 
We did not have any problems with the location. We enjoyed being close to the MUNI and BART station on Powell. And we also walked quite a bit and found the location to be very convenient to the Embarcadero, Chinatown, and some great restaurants.