I really did think about DO schools quite a bit too when I was considering SGU. It ended up not being the right choice for me, but it is good for some people.
Some of the positives of a DO school are:
1) Most are cheaper than SGU
2) They are in the US so there isn't that "culture shock" that many students feel going to a foreign school
3) They have some of their own residency programs in family medicine, internal medicine, and emergency medicine (maybe other fields too) which are reserved just for DO students.
4) DO students can apply for DO and MD residencies, FMG students can only apply for MD residencies.
Some negatives of a DO school are:
1) Almost all DO's end up in MD residency programs and thus have to take the USMLE exam in addition to the DO exam (COMLEX). DO's tend to do worse on the USMLE exam than SGU students (but sometimes better than other Caribbean schools) since their curriculum is geared towards passing the COMLEX and not the USMLE
2)Many patients do not understand that DO's are "real" doctors too and when they see DO on your ID they always ask when the doctor will be in to see them (this may not bother you but it is worth mentioning)
3) When entering an MD residency, they are sometimes required to do an extra year which is not the case for FMG's (this is true for Emergency Medicine, I am not sure about any other fields though)
4) Some of the most competitive fields are impossible to get residencies in as a DO but still possible as a FMG if you are an outstanding student.
5) D.O. is not recognized worldwide, while M.D. is. Within the US, I think there is more of stigma in the South with regards to D.O.
Here are some "neutral" points on DO schools:
1) A lot of the DO schools have even lower grade/MCAT standards for admissions than SGU (I considered this to be a negative point, but some students think it is a positive).
2) Some residency programs will take DOs but not FMGs and there are about an equal number that will take FMG's but not DO's
3) For most fields, you are equally likely to be successful in gaining a residency if you are an FMG or a DO if you are a good student
4) The "stigma" surrounding FMG's and DO's is about the same (Although once you are an M.D. after training no one really cares where you went to med school).
some other AOA residencies that i have seen are ENT, Ortho, NeuroSurgery, Anesthesia, Derm, Radiology, OB-GYN, Peds, Urology and like you said you can apply to any ACGME residency. So as a DO you can be the same type of doctor an MD would be.
http://opportunities.osteopathic.org/search/search.cfm
Also a lot of ACGME residencies that aren't top university programs(places that IMGs and FMGs apply to) will take COMLEX scores instead of USMLE scores so there's no need take both exams. Although a USMLE score will help it's not necessary.
I don't think the COMLEX is that much different than the USMLE they just have an extra section on manipulation to learn otherwise the curriculum is exactly the same and many DO's use USMLE books to prep for the COMLEX. IF you do well on the COMLEX you'll do well on the USMLE.
Patients in the hospitals don't really see your name tag (if you're in clinicals you should know this.) and when you introduce yourself as Dr. Smith than they don't ask you when the doctor is coming cause they know you're their doctor. but when you're asked where you went to medical school which people still ask and will always ask you say Grenada they'll ask where's that or why did you go there? I have had that happen to me multiple times. While if you tell them I went to med school in NY as a DO they'll be like oh cool, my cousin lives in NY. Also with the fast rate of growth from the DO schools pretty soon everyone will know what a DO is and you won't have to say anything to them, while they're still not going to know where Grenada is.
I know DO's in some of the most competitve fields. And most of the "competitive" specialties DOs have their own residencies so they can apply to both and almost double their chance of admission in them. I mentioned them at the beginning of my post. So I think FMGs are at a huge disadvantage there.
If your goal is to practice medicine in the US why would you care that as a DO you can't practice in Zimbabwe or anywhere else in the world? And with the almost exponential growth of DO grads and DO schools pretty soon everyone in the US will know who DOs are.
lastly I feel like you will have a much better chance to match in the US if you did your training in the US, i.e. went to DO school. in the 2009 match nrmp said the match rate for DO's was 70%, compared to the FMG match rate of around 50%. Although SGU's match rate was 80% the chancellor did say that he was concerned that the rate was declining.
I think pretty soon i.e. a few years from now with the growing number of both US MD grads and DO grads it will be very hard for US-IMGs to match, and if you need a visa then your chance will be almost 0%. The US Program directors don't trust the education that we get in foreign med schools, they think that foreign schools are inferior to US schools, this might not be the case for SGU, but it is for most other carib schools. So US PDs will prefer those students that went to school in the US i.e. DO's and MDs. and besides if you can be virtually any type of doctor as a DO why would you risk going abroad? just cause you're so stuck up that you want an MD behind your name? That's a pretty dumb reason if you ask me.
I picked SGU because when I was applying to med schools DO's didn't have those specialty residencies that they do now and i didn't want primary care so I went to SGU. if I was applying now I would have totally gone to a DO school. letters behind your name don't mean anything to me as long as I can get my dream specialty, and if it's something competitive you have a better chance from a DO school because 1) they have their own residencies and 2) they don't attend a foreign school (US medical school is the gold standard if you want to practice in the US, and both DO's and MD's go to medical school.)
So you were slightly off in some of your info but for the most part as of now you're correct. DO's and IMGs are both lower on the totem pole than US-MDs. and both have their stigmas.