I donno.....we've taken the interstates thru the Atlanta area at least 4 times in 4 different years...never a traffic problem (unless you think INCREASED traffic is a problem) we just ran the thing. Just like any other interstate roads.
I-40, I-20, I-10...just remember that during the winter, 1-10 (furthest southern route) has more cg open for overnighters...I-20 comes in second...and I-40, with the exception of, say Nashville, has the least open during the winter months.
Make sure you have some water (we carry 4 gallons of water (in 1 gallon milk containers) with us most of the time) and your propane tank(s) are full....for heat.
Enjoy the trip!