UCSD Pre Med acceptance rate:
http://career.ucsd.edu/undergrads/interest-areas/pre-med.html#Medical-School-Admissions-Data
UCLA:
http://www.career.ucla.edu/Students/Resources-Reports-and-Media/Med-School-Stats
However, UCLA has much less number of applicants than UCSD. UCSD has 2.5 times higher. Probably UCLA has restriction on pre med advising.
Maybe USCD is better.