Five years worth of replacement cost coverage is AWESOME!
A disappearing deductible works well on private passenger vehicles, but it's probably unnecessary on a motorhome. If you sustain collision damage: it's probably not going to be just a tiny little dent...
Unless you "broke the bank" when you bought the rig: a $500 or $1000 collision deductible (Or even more!), is probably a smart way to go!