I'm a first year med student at PSM. All I can say so far is that I love it here. The classes are small compared to the mainland med schools (60-65 students in each class of the MD program). Having a small class size really allows everyone to become very close even before classes actually start. In general, there are many students from the mainland that represent many well-known universities (e.g. Michigan, University of Georgia, Boston College, Duke, University of Miami, Wake Forest, etc...). Also, much of the class also comprises of Puerto Ricans who both went to college outside of PR or studied in PR. In all, the classes seem to be very diverse compared to what one might experience at Ciencias Medicas (because of their exclusive residency requirements). Also, the learning environment here at PSM is very positive and collaborative. The faculty is very "pro-student." You won't find many cases of students being cutthroat or overly competitive with their peers. Instead, people help each other within their class and even among different classes. (We have 3rd year mentors and 2nd year "padrinos" who give us compilations of old tests, notes, and other resources to use to study.) The students at PSM seem very happy to be in medical school. Sometimes, med school here reminds me of high school. I don't know if that's a good thing or a bad thing though.
As far as academics is concerned: In previous years, PSM has been very competitive with the other two accredited medical schools in PR in terms of the USMLE Step 1. You may want to get the pass rates of each school to get a feel for how well each school's students prepare for the USMLE.
I am sure you will get a great education at any of the PR schools you choose to go to. Your use of your time and resources are the two main factors that produce success in medical school...more than the institution you attend.
As far as Qualifications at PSM: There are only 60 seats for the entering 1st year MD class; therefore, it is very competitive. However, check the website to get the current minimum gpa and MCAT. In my opinion, if you have an MCAT above a 20, a gpa above 3.3 (approximately), and a solid resume of clinical/research experience, not to mention fluency in Spanish and English, you will be looked at as a competitive candidate. In my experience, APPLYING EARLY makes a huge differences in your chances of getting accepted.
Let me know if you have more questions about PSM.
Good luck,