It's sorta funny how no one seems to remember that I have one, single coat of Z5/ZFX and one, single coat of Z2/ZFX on my 2002 Tahoe. Just as a refresher:
- I bought the 02 Tahoe on October 30, 2001. I washed it, clayed it (I would do this no matter what, so it's not a Z prereq), and then I got out the Zaino. I applied one coat of Z5/ZFX, removed it, QD'd with Z6, applied one coat of Z2/ZFX, removed it and QD'd with Z6.
That's it. Nothing else. Then, I let my wife take ownership/driving rights of the vehicle. She works at an animal shelter and as such she parks in a gravel parking lot, chases dogs, cats, foxes, etc. through fields with the truck, and occasionally runs it through the automatic car wash - no wax, just the wash.
That said, on April 1, 2002, I finally applied a second coat of Z5/ZFX, and a second coat of Z2/ZFX. When I applied the second coat, the Z was still beading water (very tight, tiny and deep beads - like little thumb tacks), and it still felt very smooth. Therefore, it would stand to reason that the Z was protecting. From November 1 - April 1: Snow, salt, rain, dust, gravel, mud, sleet, sand, car washes, etc. = still protecting on 1 coat of each.
So, I went 6 full months on a single coat of each, and my wife abused the heck out of the truck (by Autopian standards). Sure, I'd wash it weekly with P21S (at first), then Z7 after a few months, but the point is it survived 6 full months on a single coat, and it held up very, very well.
P21S lasted about 6-7 weeks in a static environment, but it looked better than every wax we tested. I'm certain that given the ease of use, the decent durability (for garage queens), and the fact that it doesn't stain trim, it's a no brainer for me...I'd offer the customers P21S. They'll love the look, and you'll love how easy it is to use.
Sorry for long post.