I trained at UCSD and teach at UCLA. The comments here are fairly accurate. I'd say UCSD values work/life balance a bit more, but not substantively. They will definitely both work you hard.
I got fantastic therapy training at UCSD, but mostly because I actively sought it out (it's not spoon fed to you). You'll be with more MD/PhD's at UCLA, but both emphasize research. UCSD has much more community training/patient diversity. However, the lack of real electives in 4th year has been a consistent criticism of UCSD. UCSD's new PD I know well and will be a warmer presence than UCLA's PD (who has a reputation for not holding hands of residents, if you get me). Overall you'll be fine at either for getting jobs, fellowship, research opportunities, or therapy training.