I love that area and find myself down there several times a year. The roads are normal width and the curves wide enough that you shouldn't have any issues staying in your lane if you pay attention. The scenery can be distracting, and some seem to get nervous about the lack of wide shoulders. Given the high number of rental units you see down there though most seem to do really good, and I've never seen any of the tractor trailer drivers seeming to have any issues.
I remember my dad taking me through that area back when I was a little kid and you had to take the dirt road over the devils backbone which was quite the trip back before they paved a road over the hogsback.