A few years ago I rented a class A RV and on a trip to Vernon BC to visit my brother, I mistakenly believed the route that google maps gave me... it was a harrowing collection of narrow roads and hairpins...
switchbacks.. we have those on a lot of roads out west... not to much the interstates but some of the state highways in colorado you'll find them... not sure if id run a 45 foot RE or not.. and def not that fast.. id have my trans in 1st or 2nd and let the bus drive its own speed..