Best Roads for pulling a travel trailer from Vicksburg MS to Hot Springs AR

I see that there are 2 choices of roads to travel from Vicksburg MS to Hot Springs AR: 

1. US-65 OR 2. I-20 via AR 7 & 9.

The routes are about the same length.  I am just wondering which road is easiest to drive as far as going up mountains goes.

Is one more step than the other or less twisted with curves?

Any assistance you could offer would be greatly appreciated.