I dunno.
Me as a reference.
Middle aged. Went to Carib school (not one of the big 3). Step 1 = 77 first time, Step 2 Ck = failed first time , second attempt 81, CS = passed first time.
During 4th year - 5 applications, got 4 invites. Walked out of one interview after politely telling them I was not interested. I had no clue what I was doing. I then failed step 2 ck, and withdrew from the match - not realizing I could still scramble. I had no idea what the scramble was.
1st year out - got one interview invite out of something like 100 apps. Did not match
2nd year out - had a good grasp on what the match was all about. Had it down pretty slick, and understood what PD's would look for and how to "sell" myself. Had a 3 step process down to schmooze PD's - got something like 14 or 15 invitations to interview, had 2 prematch offers.
Resigned from residency.
So now I am old, FMG, mediocre board scores (being generous), 3 years out - so far one invitation in the bag, and one program called me today to ask me some questions.
Statistically - if you have 10 interviews you have something like a 91% chance of matching as a FMG.
Depends on the programs you apply to. Of those that have a significant number of foreign trained graduates there seems to be 2 main groups. 1) those that want foreign born foreign trained, but non-Caribbean grads. I think they feel those who went to schools in their own country will be the best students from their country, and that US born Carib schooled students are poor students who could not get into a US school. 2) Those that prefer Caribbean schooled United States born students, because they will have done all or most of their rotations in the US hospitals - these students are already very familiar with how US hospitals work. Foreign born IMG's often are very lost in US hospitals. I would not think it is that different but have observed it to be so, and when talking to them they feel very out of place here. Plus with foreign born IMG's there is often a language barrier, which is not present with US born Caribbean trained FMG's.
So one of my advices is to look at a programs website - specifically at their residents bio pages. If 1/2 of their residents are Caribbean trained and you went to a Caribbean school your odds of success are much higher than if they are 1/2 IMG and all the IMG's were born and schooled in Russia, or Pakistan, or India. If none of their residents are IMG/FMG your chances are zero. Next look at their visa status - if they have a significant number of FMG/IMG but offer no visa's your chances are much better.