The only thing I don't like about Zaino is their product names. I have a hard time keeping it all straight, Z2, Z5, Z6, etc. I do use ZFX and like its effect. The first bottle I bought only lasted for a couple uses though; while there was plenty left afterwards, months of it sitting in the cabinet led to it being bone dry. I don't know if the lid wasn't on tight or what (most likely). Still, I liked it enough to go buy more...
IMHO, the best thing about Zaino is it lasts a long time, makes it a good choice for my daily drivers.