I only interviewed at UNECOM when applying and I really don't remember what the teaching sites were, but I vaguely recall you had to move around quite a bit. I did not interview at PCOM, but I think they have core affiliated teaching hospitals. If that's not true, then this is a moot point, and I apologize. Full disclosure: I ended up going to an allopathic school in CA, however, at the tail end of medical school now and having met many students on my rotations who have had to go from hospital to hospital and even to different cities or states on rotations, I think that the benefit of core teaching hospitals is underestimated by most premeds.
Practically, there is a learning curve each time you go to a new site and you will not perform as well while you're learning a new EMR and trying to figure out where things are -- it gives you less time to shine when you're on clinical rotations and are trying to get strong LORs/evaluations. Additionally, it's just a pain in the butt to be scheduling away rotations or relocating frequently and distracts you from more important stuff on your plate during rotations.
On a more general level, when you don't have a core hospital, depending on the relationship of the site to your school, attending physicians can feel a lot less invested in your education and there will be less continuity and potentially lower quantity/quality in the didactics/teaching on your rotations. Students I have met who have had to go from hospital to hospital often end up short-changed on fundamental parts of our education, b/c there is not a single curriculum throughout all of the sites -- you might get educated on sepsis at every single medicine rotation but graduate without a solid discussion of working up/treating endocarditis because there is no established syllabus through all the sites like there is when rotations are strongly tied to your school.
Students of schools without a full service affiliated teaching hospital can also end up shortchanged if they want to pursue a field that is not academically represented at their main teaching site. I'm going into Neurology, and it is not a required rotation at many DO schools (ridiculous, to me, b/c it is a very DO friendly field). Some peers I met along the interview trail have had a difficult time getting quality LORs for residency b/c there is no Neuro chair or established dept affiliated with their school -- so then you have to get your LOR from an away rotation and you can't get a chair letter (required by some programs in some fields). They have to get all of their LORs from away rotations, and when you sign up, it's usually a gamble -- you lack the info you'd have about the attendings at your home institution, you are often at a new hospital struggling to learn the system while trying to show off for your LOR, and then you have to worry about a qualitative difference in LORs they write vs what they write for students at a home institution where they have a vested interest in getting them into a good residency. I assume these issues extend to a lot of other non-primary care fields, and for what it's worth, lack of home institution seems to be a major regret among my friends from postbacc who went to such programs.
While I thought UNECOM seemed friendly and quaint at my interview day, I have not seen it represented at all on the interview trail. I'm not going to go look at the match lists for both programs, but I get the sense that PCOM is better received out in the academic hospitals, so if that's where you think you might be headed after med school, you should probably go take a look.
