There are two things nice about living in L.A. IMO.
1) You can live and work in a exurb and never go into the City (and still work for one of the largest well paying corporations in the world or a hot start-up).
This is a lot harder for the moment in and around SD.
2) flights out of LAX are much much cheaper (and a lot more non-stops).
Also buying or fixing a Car seems a lot less expensive in L.A. as well.