Actually claying alone gets ALL contaminants off the surface. A paint cleaner is for getting defects out of the paint like scratches, oxidation, swirls, and water spots. Theres a much greater difference between cleaning and prepping. Prepping is removing tree sap, fallout, dirt, road grime and tar, paint overspray and other environmental contaminants, that's where the clay bar comes in. Cleaning the paint, which is using for example meguiars ultimate compound, meguiars or mothers scratch remover, or meguiars swirlx swirl remover. Im just pointing these out. ALOT of people misunderstand this or don't know what product types to use because they have no idea. obviously that's where I or someone in my profession comes in. We help steer someone in the right direction. You can ask me any question, and I will more than likely give you an honest and correct answer because ive been there and learned from the pros to be where I am today in detailing. Ive been a professional detailer for about 5 years now and I have it all mastered by now. Sure im 23 years old, a young gun, but I learned early. I started taking a keen interest in detailing when I was about 15 years old, by the time I was 18, I had it all down to science. Im not picking an argument here just to let u know, as I stated earlier, im just giving some details. Idk how much u know about detailing, but I want to correct you on this and help you understand the differences. Claying actually does the most work between the two.