So my question to you is, is it best to go into Ross Medical School or a Puerto Rican Medical School ?
If I recall correctly, three of the four Puerto Rican schools are currently LCME accredited. So, if you go to one of those, it is not a fair comparison. You will not be considered a "foreign" graduate, and will not have the same regulatory problems that an ECFMG doctor has (not that they're terrible, just an extra PITA). So, all things being equal, going to a LCME accredited program in PR is a better choice.
To answer your other questions, I am a success story. I make a lot of money in a field that, although has its own issues and is getting "tighter" if you will, has a long history of providing one of the highest compensation:hassle ratios. Having said that, I could pay off my student loans right now if I wanted to. But, this is a better question for a financial planner than myself. Suffice it to say that there is a lot to consider (e.g., how long your loans are, what the interest rates are, how you amortize them over the length of the loan, etc.). My money not dedicated to my lifestyle (e.g., home, car payments, vacation travel, etc.) is currently earning me more through my investments rather than paying off my loan.
Primary care is not really frowned upon, per se. I think this perception is because, as of right now, these specialties are less lucrative overall. This may be changing, but I can also tell you that the "new paradigm" in practice management is to have corporations buy practices and essentially hire you back at a salary with little to no control over the daily aspects of running your practice. Some people like this; other people hate it. It all depends on what you want, what your life plans outside the hospital may be, where you want to practice, etc. In that regard, your pedigree will open doors in places that you otherwise might not be considered. Yes, some future employers are degree snobs. You will never get away from that. And, a lot of connections you make in residency will prove to be some of the most important ones... for the rest of your life!
I admire your work ethic. You will do well if you provide the same level of effort to your medical education. This is the "failure is not an option" mentality that shows success. I will tell you that it is admirable to pay-as-you-go, but having secured low interest rate loans that you can pay off over time is also a viable financial option provided you succeed in your field of endeavor.
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