As far as I can tell all this stuff does is dry on your wheels and make it another layer harder to get them clean. They like to disparage the other products that magically change color. Whatever, I'm switching back. I'm tried both multiple times on two older BMWs, a classic Porsche and a 97 Land Cruiser. So, my semi-professional opinion is given the choice, just use concentrated car wash over this. Picture shows product dried to an X5 wheel basically in the time it took to suds up the rest of the car. On a cool foggy (summer) San Francisco day.