Shirin's Place is great. The location is very nice and the Mission District is well worth staying. You have so much to do and see there, that I wished I could have stayed longer there. There is a Bus-Stop right in front of the door and a Barth station about 10 minutes away by foot. The room is big enough, and even though you share the bath and toilet with the other people living there I never had to wait. Shirin was very nice and friendly and gave me some good tips for food. Every time we met (usually when I was leaving) we had a nice chat. She was always very pleasant to talk to and has two very nice cats and two very lovely dogs, which never bothered me at all.
I would definitely stay there again if I am coming back to San Francisco.