This was my first marathon and I'm so glad that it was! I enjoyed every second of it!
T-shirts: Super cute, wish they set it up like New York though, where you try on the shirt first and then pick which one you want. Trying to exchange shirts was kind of a cluster.
Aid stations: Great!
Course Scenery: Very pretty, a great view of Chicago.
Expo quality: Good! easy to get through
Elevation: flat course!
Parking/access: my hotel was across the street from the entry points (stay at congress!)