I have the Mother's clay bar kit. And it does make a difference. Try it and you'll see. Before using the clay bar, run your hand over the surface of your paint. It probably won't feel super smooth. You'll feel the contaminants embedded in your paint. Then use the clay bar on a small section of paint and dry it. Run your had over that section again. It should feel dramatically different, much smoother than before. I was amazed at what they remove from the paint.