I know that someone on here has installed the rear deflector and posted about it, but darned if I can find that post. The dealer installed mine, so I can't comment about the ease/difficulty of the install. However, I do believe the product works as advertised. This may be an apples and oranges comparison, but the Cherokees we use at work (which don't have the deflector) accumulate an impressively thick layer of dirt on the windshield in a relatively short amount of time. Mine is spotless by comparison. Sorry that I can't provide any more info than that.