Been there from i-77 to Bristol ,then Bristol to Knoxville,at that time with 1/2 ton chev,and 22' tt Most were headed to race, sooo,all were driving too fast, and a lot o traffic. But I think at reasonable speed it is nice to ok drive.On the other hand, heading to Bristol may have cast a more favorable tone, either way nice country there.
I've driven I-40 between Knoxville and Asheville many times, in cars, towing a pop-up, and driving our Class C while towing a car. I've never had a problem with the drive. Just be careful with your speed and save your brakes. Rock slides could cause lane closures at any time, but they have it set up to switch traffic to either side.