Well, it's a city a lot of people like but certainly those adjectives could be applied to just about any good-size city--and it's why a lot of people also don't really like cities period. I'd add that, if your experience with SF is going to a show at the Moscone or elsewhere nearby, that general area (Market, Tenderloin, etc.) is definitely less nice than much of the rest of the city. But it's also fair that SF, for a variety of reasons, also has more street people of various sorts than most cities do.