I recently switched to Collinite, and I found that 1)Collinite doesn't stain and 2)Not only does it not stain, it removes the stains from other waxes!!, and 3)It can even work as a trim dressing!
While I haven't tried it on *my* MPV (I use the Klasse twins on it), I used Collinite 476S on the rubber bumper covers of the Volvo for ages. Worked fine for me too.