re: Car wash foam cannons - yay or nay?

I just started using a foam cannon a few months back when I bought a black truck. Using foam and a pressure washer as a prewash makes the rest of the wash a breeze. I am very picky about preventing swirl marks so the foam and two bucket wash method has done great. Btw - I bought a cheap $26 armor all cannon from Orielly’s and it is sufficient. You can watch the dirt fall down.