We leave the 27th of Aug. on our first trip with our brand new 2010 29rk Cruiser. We will be going over about50 miles of gravel road, slowly. Was thinking about one of those rock guards to go on the back of the truck to try to stop rocks from chipping the front of the trailer. We had an oldTT that was beat up pretty bad, we didn't know if 5ers would get as much rock damage as a TT would. WhatI would like to know is, are they necessary or not necessary and what kind is best, preferably one easy to put on and remove.