I was born in Los Angeles.
Los Angeles has lots of great food, great weather, more things to do than you can imagine. Want to go paddleboarding, you can totally do that. Want to go create your own perfume for a day? You can do that. What to go indoor skydiving? You can do that. Want to swing by and see celebrities at a movie premiere? You can do that. Want to rummage through huge treasure filled flea markets? You can do that. There is a scene for every single person out there, whether you're a nerd or a hipster or a druggie or an evangelical Christian, you can find your people in LA.
Los Angeles is also very dirty. There's significant racial tension. There is violence and crime. Police corruption. The traffic makes even the calmest people enraged and murderous. There is a higher concentration of shallow people (but really, only in certain circles).
I love LA. Even with all it's flaws. But I am glad I don't currently live there. It's very nice to visit though.
I currently live about 10 minutes outside of San Francisco.
SF has hippies. People here are very outdoorsy. Everyone hikes or bikes or runs. And everyone has and loves dogs. People are generally mellow and friendly. But probably not midwestern levels of friendly. It's very very beautiful here. I'm sometimes awed by the beauty that is in such easy reach. The food is tremendous. There's a great art culture. A lot of people are very tech-y, half the people you meet will either be starting their own small business or launching a new mobile app or tech company. People can be a little pretentious with their, "oh you don't have vegan soy milk here?" type of thing. Lots of hipsters. Stunning museums and architecture. Lots of fog.