I lived in SF for 5 years. Its good and bad i guess. I was mostly living out in the Richmond district. Pretty mellow were i was but then again there was a chinese-gang shoot out on my street. One kid died across from my door. They didnt find out who he was because he was an illegal from China. ****ing wierd.
Living in Tokyo now..the land of ZERO crime. Very different. You dont really even need to lock your bike in most areas. No one would even think of stealing it.
Probably moving back to the bay area next year though. Gotta buy a gun.