I try to give you the benefit of the doubt but your posts sure sound like Zaino ads most of the time. :nixweiss This thread wasn't about Z-CS vs Opti-Seal either, the OP had a simple question about OS but you turned it into a comparison thread that seems like you are pushing the Zaino version.
I have no dog in this hunt, I use what gives me the best combination of cost, durability and price. And yes, I do use some Zaino products like AIO and Z5. I got some Z-CS for free (full bottle, shipped directly from Zaino) so don't you think if I honestly believed it was a better product than OS, I'd be using it? Why use something that costs me money and doesn't work as well as a free product, right?
Side by side by side on the same car, I could tell no difference in durability on a soccer mom abused 740 between OS, ZCS and UPGP. At 3 months when the car was traded in, all three were beading fine (not one I typically use ONR on either).
Z8 has about 3-4 weeks of durability for me, which seems a typical result. Are you really saying that Z8 is the most durable product in the Zaino line? Or just compared to other spray sealant type products? :think: