These products were the forerunners of all the great products of today.
If you ever really got into using their polishes, you really learned the definition of what a
"thin coat" is, and found that less is really better than the old adage - " if a little bit is good, then a lot more is going to be better"..
And you learned about application techniques that were long, straight, even pressure, thin, so thin you could barely see it if ever, and using vertical, straight strokes on the vertical panels - fenders, doors, straight areas of trunk lids, etc...
Imagine a Clear Sealer spray that you just wiped on with very thin coats (like all their products), and let it dry and cure. What a concept!

Years ahead of its time.
I think a lot of people got confused with the mixing of the ZFX, a dark blue product in tiny little plastic bottle, that was the "hardener" if you will, of the Z-2 Pro or Z-5 pro polishes. It was so simple, I think it made people crazy and they missed the point of how easy it really was, to just put a couple of drops or so out of that bottle into the measured amount of Z2 or Z5, and shake it up. Nothing could be simpler than that.
If you ever had a local Zaino rep around that was really into the product, you would be stunned at the depth of the zaino product/s on his paintwork of his car. It was like someone sprayed a bunch of extra clear over the top of the paint.
Used all their products for years even before these Forums were invented, and online shopping came into being.
Their Leather Cleaner product will always be one of my favorites. Combined with steam through a white towel after brushing it into leather with say, a SwissVax leather brush, its pretty unbeatable for my needs.
You will notice that Sal Zaino has never deviated from his original business plan pretty much, and to the details of not even wanting to sell some of his products in larger sizes - even to Detailers..
I hear he and his family have done pretty darn good over the decades, and still going strong.
Dan F