When traveling from Seattle to Boston, to use Highway #2 to Sault-Ste-Marie to Montreal then down 35 and 89 to Boston? Rather than travel the major highways in the US and pay the tolls? yes we know ...
If you don't actually go through downtown, Chicago isn't that bad. If you get off I90 in Rockford and take I39 south to I80 then I80 east to hook back up with I90 in Indiana, there is not much construction to go through (a little on I39 and a few miles on I80). The mess where I80, I90, and I94 all come together has been redone a few years back and moves pretty well most of the time.
Going through downtown on I90 is painful in the car, I would not attempt it with the MH. Except maybe at 3:00AM.