Where exactly in the San Francisco area are you? For instance, if you lived in San Francisco proper I would say that mandarins are very unlikely to ripen. I live in Novato (north bay just south of sonoma county) and have successfully gotten satsuma and kishu to ripen. There are many types of satsuma, the most available of which is owari. I am not a big fan of the flavor of owari, but some people really love it. Kishu is a small seedless mandarin the size of a golf ball with a great, Clementine-like flavor. Tango, another seedless mandarin, probably doesn't get enough heat in the bay area to ripen consistently. Hope this helps.

-Brett