You'll get much more clinical exposure to a larger variety of cases at UOP, not because of patient pool, but because we don't house nearly as many specialty programs as UCSF. I know UCSF has implemented a new curriculum in the past couple of years, don't know if they bumped up the requirements. But I had a couple friends who graduated before having only done 2 endos. I know several 2nd year students now (only 2 quarters in clinic so far) who have done 3 endos already. I'm not sure about UCSF, but at UOP, production matters for grading and graduation. If we don't make a certain amount of $$ for the clinic, we're not considered efficient enough.
My one concern about UOP when I was applying (other than outrageous cost) was from a shadowing experience. There was a recent UOP grad working at the office and he was performing a certain procedure on a child with primary teeth (can't remember what the procedure was since it was a while). When the Main dentist came in, he said "What the $%^& are you doing!" It seemed that there were multiple ways to go about this procedure, and the UOP grad was only taught one way. This one way is not how you are suppose to treat the primary dentition, and irreversible damage was done to the teeth. So whenever I hear about how great it is to be out in 3 years, I always think back to that incident. DOing a million procedures and being super efficient does not make up for adversely affecting your patients health with your lack of knowledge.