As someone who also has a huge interest in urban policy, I have practically ruled out Harris at this point. Conversations with two unsatisfied students (with similar interests to mine), plus the fact that Harris' curriculum is quantitative almost to the exclusion of other relavent disciplines needed for sound policy analysis. Also, while Harris is located in Chicago, it actually has few links to the City, certainly nothing like NYU or USC's engagement with their respective metropolises. I went to UChicago for undergrad, and never noticed a Harris School presence in any of the community development or urban policy initiatives I got involved in.
That being said, I'm confident Harris is trying to change this reputation, and will be growing its "Urban Policy Initiative" in the near future. The new Institute for Politics with David Axelrod will certainly bring more discussion of local politics to the school.
Good luck!