The Westin River North is not as convenient as the Westin Michigan Ave to shopping but is closer to several excellent restaurants. From what I've been told it's much nicer in the rooms - it's a former Nikko.

I would avoid the W Downtown because both its in a business district that's dead on the weekend, plus looking at it in travelocity I found that they have 175 sqft rooms as well as 350 sqft rooms. For an award, I'd be concerned that I'd be stuck in one of the smaller ones.

The Sheraton looks nice, but it's a few blocks from most stuff.