I guess the big difference for Zaino is the number of coats you have to put on to reach that deep glow that a carnuba can give you with one coat...you may never reach the "glow" of a carnuba either.
I did put another coat of Z5 on my CLK and it is looking better. The trick with Zaino is the number of coats I guess. I don't have the time to put all those coats on for every car though

. Looks like for now I'll stick with Z and experiment w/ BF II when I get the chance. Thanks everyone for the help!
