I agree, but the clay bars you get with the kits at the auto parts place are way too small and are only good for one panel if you have really contaminated paint. You can buy a large bar (about the size of a soap bar) for about $20 on eBay and it's worth every penny.
With best regards
Al
1970 Mercedes Benz 280SL California Coupe
1971 Mercedes Benz 250CE (RHD in the UK)
1971 Mercedes Benz 300SEL 6.3
1973 Mercedes Benz 280CE 4 speed
1973 Mercedes Benz 350SE 4 speed
1977 Mercedes Benz 350SLC
1979 Mercedes Benz 450SEL 6.9
1979 Mercedes Benz 450SLC 5.0
1981 Mercedes Benz 500SLC
1973 GMC LWB Pickup
2006 Adidas Samba