I don't mind curvy roads as long as they're built for trucks, I worry about getting stuck on those small mountain roads where there is barely any room for 2 trucks to pass each other, or smaller.
I get more concerned with the sharp inclines/declines. My truck can pull up them but I just don't like to push it if I don't have to. 199/299 don't sound to bad. I'm usually fine going up and down the passes we just had a bad experience last year going into Clear Lake, CA. I don't even know what road we ended up on but we made a wrong turn and ended up following the GPS (TomTom) up and down some insane mountain roads, it was no fun. Just looking to avoid that.
If a road is a normal truck route then we're usually fine on it.