Top 3 on reputation/perceived competitiveness are going to be in some order:
UChicago, Northwestern, Rush. I didn't interview at any of these so I won't comment further.
Loyola probably comes next, some may count it with the above. Great facilities, awesome gym. Very nice place to be. Strong group of residents.
UIC I thought was great. As apma said, very happy residents. Nice location (they're all in about the same place minus Loyola which is a few miles down the road and not accessible by the L). The faculty also impressed me, very nice and down to earth. Not as pretty as Loyola, but I ranked this one really high. In fact I almost put it number 1. I would have been very happy there.
Illinois Masonic- Doesn't take too many through the match making those 3 spots in the match harder to get. Location can't be beat (Lincoln Park area I believe) and they offer housing at ridiculously low prices. Nice facilities. Obviously the name isn't there, but the PD is a big name in the gas world. Would be a nice place to train.
Cook County. Didn't offer me an interview. I really don't know where to put this one. Pre-match I thought it was less competitive.