When I was flying back and forth from MO to WI it was my experience that RFD appr were even bigger jerks than CHI appr. They dropped me on nearly ever trip if I was using FF instead of flying instruments.
Did you ever talk to Chicago Approach? Probably not - You'd have been talking to Chicago Center.
Maybe Chicago Approach is the nicest bunch of people in the world - But I can't tell because they won't talk to me.
Apparently a lot of training goes on at RFD. I would regularly listen to RFD appr being absolutely brutal to someone flying approaches. One day it was a citation shooting approaches. The approach controller had the pilot so upset that I wondered if he was still safe to fly. It was so bad that I called the supervisor and asked her to review the tapes as soon as I landed at ATW.
They're not nearly as helpful and friendly as those at MSN, but I've never had them (or even heard them) refuse flight following. And part of the reason there's so much training going on in RFD's airspace is that all the instrument students in the Chicago area are getting booted out of Chicago airspace on a regular basis and have to go somewhere else - I think RFD is closest for most of them, though MKE and/or SBN can be depending on where they are.
I've only heard about some of the controllers out east and haven't experienced them personally.
It doesn't seem like the region really has much to do with how good the controllers are, it really varies by facility. We have excellent controllers at MSN, and I've had exceptionally good service from NorCal, New York, and Houston as well. Chicago is generally the biggest pain, but Milwaukee, Philly, and others have made it onto my not-so-great list.
I am talking about the TRACON (Approach) facilities above - Centers are generally all very good, with Chicago, New York, and Boston having given me "above and beyond" service at various points and only Seattle being a pain (refused a handoff from PDX departure and then refused directly when I called up) - But that's based on extremely limited experience with them (yes, one encounter).
I'm glad that seemingly the vast majority of aviation-related government people I've dealt with are extremely helpful and friendly (ATC, NACO, FSDO, etc) and really do not fit the government employee stereotype.