As requested here is one example...
Here's one example:
Zaino and PPF - Club Scuderia - UK Ferrari forum for chat, meets and events
There have been threads about this all over the internet for years, along with others that support the product. Naturally the ones that are supporting it have black, blue, red, yellow, etc colored cars, so of course it doesn't make any difference. Keep in mind, that I am not saying there is anything wrong with Zaino, just as I am not saying there is anything wrong with Windex. But I wouldn't use either of them on my carpet, because I have another product for that surface of the car that is designed for it.
If you have a white car, use Zaino on your paint, and find a purpose made product to use on the PPF. Otherwise you really have nothing to worry about anyway.