I'm not speaking from experience but from my own research into this subject. As for residency, it will be more difficult, but a good USMLE Step I score will open up doors. As for choosing where you do your rotations, I think it's partly up to you and partly up to chance. I almost went to SGU and understood that you do not simply pick where you do your rotations, though you do have input. As for things being harder, it will be a bit more difficult. Don't, however, listen to all the naysayers. I'm going to a US MD school, but I would certainly consider AUC, Ross, or SGU if necessary. The person that interviewed me for SGU also told me to try and keep track of attrition at other US schools. Transfer spots are available but only when someone drops out. She said that many people from SGU transferred to Miami, and that the dean had close ties with that school. There's a good chance that each non-US school has slightly different transfer opportunities. Whatever happens, just work hard, don't get discouraged, and you'll land a spot in emergency medicine, even if it doesn't happen overnight.