Faced the same decision two years ago with Michigan, UNC, and NU. I strongly encourage you to visit UNC and Michigan if you can. I was dead set on NU, literally minutes away from putting my deposit down, until I went to Michigan Campus Day. Everything changed. Just finished up my 3rd term and I absolutely love this school.
I really liked UNC too, more than NU to be honest. Very very similar in many different ways to Michigan. However when you really put them up against each other, Michigan definitely edges out UNC. I was never a fan of the academic scandal and the extreme intellectual disparity between the OOS and in state students there.
Anyways, you are in a situation where whatever school you chose you are going to love and receive an elite education at the same time. Congratulations. Go Blue!