I would like to put in a +1 for CHM, although both are obviously good choices and you can't really go wrong with either of them. It seems like it comes down to personal preference as far as what you value regarding the city you'll live in and the hospital you'll be working in. I just want to address some things that as an M4 I appreciated about CHM and that I couldn't really appreciate as a pre-med or before I actually started med school.
First, I don't think a "learn on your own" curriculum is a con at all, you're going to have to learn on your own no matter which medical school you go to. No medical school curriculum as far as I know is tailor-made to only boards-relevant content, and you will spend a large portion of preclinical years studying outside resources regardless. What's nice about CHM is that all M1 and M2 is P/F, so you can study enough to get the P (not difficult to do at all) and spend the rest of your time studying for boards or getting shadowing/mentoring/research experience which will matter much more come residency application time. I can't imagine how much of a hindrance having graded preclinicals would have been, and I would consider graded preclinicals to be a bigger con than a self-study curriculum.
Second, after looking at OUWB's match list and CHM's match list from last year (CHM distributes this internally, I'm not sure if it's available otherwise), they match pretty similarly if not somewhat stronger at CHM in my opinion (at least this past year). Multiple matches to Ivies, UCSF, NYU, MGH, BIDMC, Mayo, etc., and multiple matches to highly competitive specialties (ortho, derm, optho, uro, IR, etc.). Others in my class are having amazing success in getting interviews at top programs in their specialty (although the match has not happened yet obviously). Of course this varies year-to-year and is somewhat self-selecting but you can match anywhere in the country and in any specialty if you put the work in regardless of medical school, and OUWB vs. CHM is not going to be the determining factor in that regard especially if you want to remain in Michigan.
Third, and this is entirely based on personal preference, but I actually enjoyed living in EL and know many classmates who enjoyed EL (as well as many classmates who really enjoyed GR). The physical location where you are going to be sitting and going through lectures is maybe the least important aspect of any medical school. Yes, if you're in EL you will have lectures in the rad basement. And then, when that's done you get to leave and do whatever else you want. If having the nicest, newest lecture hall with a view is important to you, then CHM in EL specifically will not be the place for you, but as an M4 I can assure you that this should be low on your list of priorities. If you will be attending medical school on full financial aid (including living expenses), your money will go way further in Lansing/EL than in GR or possibly even Royal Oak, and I feel that my overall quality of life was improved because of it (decent apartment with no roommates, never worrying about being able to afford a night out or going out to eat with friends after lectures). Any city is going to be what you make of it though. If you feel that you are personally more inclined to live in a big city, then obviously GR or Detroit will be more appealing to you, and if you attend CHM you do run the risk of being assigned EL unless you have very strong ties or extenuating circumstances to guarantee the GR placement.
