This is is a question I actually don’t have hard data on. If you want a more confident answer, a professional adviser at one of Newnan’s Pre-Health Drop-In advising could definitely help.
If if I would have to give my best guess though, I would say that what school you went to sort of matters. But what matters more, perhaps, is how well you MCAT matches your GPA. For example, a student at an “easy” school might have got a 4.0, but then their MCAT score was low because their classes didn’t prepare the student very well for the MCAT. The discrepancy will be clear, and perhaps will be considered when deliberating acceptances. On the other hand, if an admissions team saw two students (one from a “hard” school and the other from an “easy” school) by the students have the same MCAT and GPA, I strongly hunk that they won’t think about your “stats” much more and rather go look at your extracurricular.
All in all, my feeling is that at non-top-20 schools, it probably important to have a pretty good gpa, pretty good MCAT, lots of experience serving people, and solid letters of rec. GPA won’t be everything. Plus, you can take advantage of the awesome opportunities for serving people in a place like Ann Arbor and the surroundings! We have great teaching hospitals that not all undergraduate institutions have access to!