The construction in the Memphis area has been ongoing since 1989....no, I'm not kidding and it's a PITA. I-40 and I-55 come together there so plan for lots of zig zags and stop and go. The last time I was south of Memphis there was construction for about 10 miles or so - hope they've finished that up. Also, some construction around Greenwood, MS...just a heads up. It should be done.
When we last came through Chi, DH set the GPS to avoid toll roads and it was a snap! Not only the cash outlay, but they charge more for towed vehicles. And the toll booths are none to wide. I honestly believe we made as good time or better, saved a bunch of $ and had a lot less stress staying off the toll roads. The alternate roads were good, traffic was not bad at all and "Scarlett", the GPS did a fine job. Enjoy your trip.