I tried some on my wifes old Mazda and it worked great! Just as good on a side-by-side (hood) comparo with Clay Magic, fine grade. NO difference. I just had to use DoDo Slippy Lube instead of just any old spray detailer. Not convinced? Then I used it on my father-in-laws red Chevy Equinox. NO marring; NO added swirles; NO issues. Why did I do this? It was eating at me to try it after I saw some in an art supply store @ $3.69 for 1 LB! And yes ... I did the plastic baggie test. I posted this on another forum and 1 guy said they are two completely different animals (detailing clay + modeling clay). May be so. Results and price are all that matters. Tomorrow I'm doing a black CTS and I won't hesitate to try it again. Purists may ban me for life, but ... Cheers!