UCSD is all about location. I was an undergrad at UCSD too. I live in SD now and love the city. The weather is awesome and the fact that the campus is so close to the beach.
However, after all my interviews so it happened that it was the last place I visited. I noticed a lot more negativity among students and surrounding the school itself. But the fact that I already live here in San Diego and that because for that matter it would be so much cheaper, this is my first choice. In three words, location, location, location.
I interviewed and got accepted in UCDavis and I am wait listed for UCLA. I am also wait listed for Einstein and Cornell. I know this schools showed "happier students" than UCSD but location beats the others. That is for me and because my family lives here.
If you don't live in SD you might find yourself happier somewhere else. when I visited the campus found the same trend like in UCSD undergrad, competive people all around. I thought for a sec it was just myself BUT....
As I was walking towards my car after the interview was over, I saw a first year and asked me "is this your interview?" I said yeah this is my first choice. She said "Oh really, are u sure? I dont like it too much myself. Did you interview somewhere else" I said yeah at UCLA, davis, Irvine. Then she said "I would kill to have gone to UCLA"
Of course take everything for a grain of salt but the fact is that she didn't look happy. Other students kept saying "people keep saying things about this school but it is not that bad, you get used to it"
Like I said I want to be close to my family and I already survived 4 years of undergrad.
Hope this helps!