You can't really go wrong with this decision. I had this same decision along with some other schools last year but the difference between UM and Duke was only 5k so by the grace of god and my parents, I was able to pick the school I liked more.
Alexandre is absolutely right regarding choosing college based on fit. In my case, I wasn't too thrilled about UM's two spread out campuses and I didn't find it as aesthetically pleasing as Duke's West Campus. I also got the feeling right away that Duke's faculty deeply care about their undergrads and that I would get a lot of personal attention from professors, which is a vibe I didn't get at Michigan. Also, the weather was a MAJOR plus for me(I grew up in the Middle East and Australia and let's just say Michigan isn't exactly the same) and I definitely like basketball more than football. The social scenes at both schools are similar with Duke's being a little more Greek-oriented. The absolute clinching point for me was the fact that Duke was located in the Research Triangle, a location which is bustling with innovation, medical breakthroughs, business and technology. For a biomedical engineer, it must be like heaven. One cannot say the same about Ann Arbor and I was afraid that I would end up embroiled in the terrible job market that Michigan currently has. Your mileage may vary.
Although I disagree with Alexandre's assertion that Michigan and Duke grads are viewed the same by employers, I think he is absolutely right when he says that you will have opportunities to succeedd in all the top 25 universities. Regardless of whether you go to Harvard or Michigan, it's your performance in college that will make the difference.
My friends at Michigan are having the time of their lives. I'm sure you will too.
