i think the general concensus on the trail was that usc is a h$%&hole!! tons of trauma, little direction. decided not to interview there. also, if you notice, you are competing for one of 5 spots. almost every year they match 5 from usc med.
i have heard good things about harbor. if you think you want to go there, you really need to do a rotation. if i remember correctly, they interview very few people for their 3 spots. overall, i have heard that it is a very well-rounded program.