I've been to San Diego a couple of times and enjoyed both visits. I wasn't necessarily looking for a nightlife or the people, but rather the things to do and the vista. I did find the food to be rather expensive in the hotel we stayed in, but it was actually really good.

I don't think I'd want to live in California regardless, but San Diego could be one of those places. But I like quieter places.

I have yet to go to Spain, but I have been to Mexico a number of times and you trade a few things for the warmth of the people and the cheaper vacationing. All in all, though, I would say I've enjoyed each trip down there.