Used the stuff on my vinyl roof too, very good and easy to wipe on. The mrs got me a waxybox ages ago and it was one of the products in there, i must say i was most impressed with the shampoo stuff, it says on the label that it wouldnt leave spots when it dried and it really didnt unlike the autoglym stuff i use.
She's on about getting me the next on that comes out, so i'll probably have some more random products to use next time.