Poor service, dirty and noisy, but affordable
This hotel was a last hotel on our road trip to California and we stayed there for a couple of nights before heading home. The experience was far from great. 
The hotel service was horrible. We asked for extra towels the night when we arrived and it took them about 2 hours to actually bring them to our room and it would take them at least 30 minutes to bring our car to us when we parked it in the valet parking.
The room smelled like a bug spray or something like that and the bed blanket was dirty with I don't even know what.
The building was extremely noisy. I understand the street noises, after all it is San Francisco, but you could hear everything that was happening in the hallway, how many times my neighbours left the room and came back. 
Overall the experience wasn't great, but the positive factors of this stay was that the price was reasonable for the weekend stay in San Francisco and the location of the hotel was pretty close to Union Square.