This topic has been discussed frequently here. A search of the forums + exploring UOP's site is advisable. I was part of the Pre-Dent program and was admitted to dental school, so I'll try to answer your questions.
Is there an advantage for students in the program?
Yes. As outlined on the website/in the course catalog, students in the program need only 18's across the board on the DAT (less than 18 on QR is excusable, as long as it's not under 15) and a 3.25 GPA (for 2+3's; 3.15 for 3+3's and 3.05 for 4+3's).
* These requirements are below what is typically considered "competitive" if you're NOT in the program, so yes, I would say they're advantages.
On top of that, a few of your biology professors are also Pre-Dental advisors who regularly speak to Dugoni dental school admissions, so they can put in a good word for you. Basically, the dental school knows who you are before you apply, which is good.
How many kids actually make it in to the dental school?
Last year, there were about 60? 70? applicants. About 30-35 matriculate. So, the 30-35 that didn't matriculate either did not get admitted or chose to attend another school. No one but the admissions staff can tell you for sure.
PROS: The dental school admissions process is a crapshoot, so whenever you have an advantage, you should take it. The Dugoni dental school is a fantastic school and otherwise very difficult to get into if you're not a part of the Pre-Dental program. The biology education you'll receive at UOP undergrad is also top notch, provided you put the effort in.
CONS: Stockton (where UOP undergrad is located) is not a nice place. But if you really really work for it, you can be out of there in 2 years so it's not that bad. Keep in mind that almost every Pre-Dent admitted wants to do 2+3, but realistically only 5 or fewer actually get the requirements done in 2 years. The rest take 3 or 4 years.
- CON specific to 2+3 track: Most of those who do get through in 2 years struggle once they get to dental school because they haven't had the chance to take upper division bio courses like Biochem or Physio. So unless you're absolutely sure you can handle the rigor of dental school with only 2 years of preparation, don't do it. Take your time.
* ETA: I should probably mention that in the past, an interview at UOP is virtually an acceptance, but the tide appears to be changing. I know someone this year who met the program requirements but got waitlisted. So, you should make sure other parts of your app are sound as well (e.g. shadowing, extracurricular, etc).
