Actually I didn't hear back from SIU till April, and by then I've deposited at UIC already. I don't live that far away from UIC so I commute, which made my decision pretty straightforward.
Even if I had to live near campus, I would have picked UIC for the following reasons. Don't get me wrong, I liked SIU too, but I felt that you have more collaborative opportunies at UIC with other health professions since the school is in the middle of the Medical District. In addition, you have a huge patient pool from the Chicago areas, which helps a lot in your D3 and D4 years. UIC has an extensive research program, and it's the only school in IL with all the dental specialties. As part of our rotation, we will have exposure to the post-grad clinics.