TWO things to say here:
I think go to SGU or the AUC if you can get in. After all, if you waste 2 years trying to get accepted to U.S. schools and don't get in you would have already been in CLINICAL rotations in the U.S. by the time you started medical school. Unless you have an MCAT of 27 or above, I'd go to the SGU, AUC or even consider D.O.
AND the second:
There is no difference in starting salary for someone coming from the BIG 4 in the Carribean. They took the same tests, passed them, and competed in residency and became 100% U.S. liscensed physicians. Your school is not even a question after residency placement and getting your liscence. There is also a shortage of physicians so newbies from India that are practicing in plastics for example are easily making 7 figures if they wish to. Also, an education at the BIG 4 is not a worse education compared to the states. Harvard Calibar? Probably not... University of Kansas-City Missouri or Ponce? Probably Better. I actually knew someone that tried to transfer to another U.S. school and got rejected while a SGU student transfered there that same year. Just goes to show...