I spend plenty of time prepping two vehicles for car shows. The vehicles aren't paritcularly spectacular or collectable...1988 Chevy Silverado (brought back from the grave) and a 2008 Mustang Bullitt (I buy American as a priority!) I have used McGuires and other clay bars and can't say they help much unless you have a dirty car that sits outside most of the time. I find that multiple coats of McGuires or Mothers wax will prevent dirt, bird poop, and other stains from penetrating to the paint. A slick wax job with one of these products will most assuredly give you the best protection and appearance.