I hate to say this but I have tried Swi. & Zym. .... I am not totally impressed with them. I keep saying to myself to try them again but when it comes down to picking up a can of wax my hand majicly goes for the PS...... There is just something about it that makes "MY" red car look great. I don't know what it is but....And I am sure others have that same majical hand that reaches for something else. Thanks OK, I understand