Just did I-80 and 90 from Davenport, IA to Rapid City, SD (and past) - with the exceptions of the comments about road construction and Chicago, you'll be fine - the road is great all the way and easy driving - no big cities, and where there are cities/towns, there is no issue at all.
I passed through a fair bit of road construction, the worst being around Mitchell, SD, but that was a month ago now, but if you are travelling slow and steady, you will have no worries!
2012 Cedar Creek Silverback 35QB4 "Silver Edition"
2011 Chev Silverado 3500HD Dually Duramax Turbo Diesel - Allison Trans / PullRite 20.5K Super 5th Wheel Hitch & SuperRails / Trailair Tri-Glide Air Ride Pin Box #21,000 /
Honda 3000i Handi