I went to a Caribbean school for a year (not one of the 4 that you mentioned) and then decided to apply DO this cycle, and so far 2 acceptances (DMU and AZCOM), still waiting to hear from Western-Pomona interview, which was the only other school I decided to interview at. I cancelled all of my other 7 interviews after I got my DMU acceptance. The point is, you should never ASSUME Caribbean=lower stats. Every person is really an individual who brings an assortment of different experiences (more than numbers) to the admissions committee and not everyone who goes to the Caribbean does so because they were denied admission to every other school. That certainly wasn't my case. I think choosing a place to receive a medical education is a very individual choice. What works for one, may not work for another. Even though there are some universal CONS to going to school in the Caribbean, there are many pluses that for SOME people outweigh the cons.
I'm just trying to get you do think outside of the box...SDN can sometimes be a pretty neurotic place. If I were to listen to some of the advice I got from here, I would have never even applied to medical school...many said I didn't have a chance, I had to redo my pre-med, retake my MCAT, basically be REBORN to get in. I decided to ignore SDN and go for it. 10 interview invites (and 2, possibly 3 acceptances) later, I'm glad I did.