Avoid. There are so much better for the price
A huge conference in SF forced me to the Powell in January 2012. The staff were fine, free WiFi was welcome but otherwise the hotel lacks almost everything. The location is very good at the base of the Powell/Mason cable car turntable, BART stop and the shops but that is simply not enough to bother even considering it. A room change at my request shifted me from a tiny room with a stains, miniscule bathroom and internal service channel view to a slightly larger room with stains, larger bathroom (no bath) and another service channel with loud defcating pigeons. Enough said. Oh and they have a happy hour!