The term "synthetic wax" threw me off. I don't consider it a wax and its not called such. To me the term means a non-wax product that looks and acts like a wax. Blackfire and Platinum are examples of this definition.
So if this term is to mean any product except for ones that are wax based (be they carnauba, montan, parrafin, or beeswax) then my vote goes for Zaino.