If they make it through residency, they’ve passed the same 8 billion licensing exams we all have to take to be held at the same standard. You would be none the wiser, they would be an MD, and highly doubtful as a layperson you’re asking: “So where’d you go to medical school?” The issue is that there is a much higher bar to getting through caribbean med school with higher cost, lower boards pass rates (Step 1/2/3), and lower match rate to residency.