I learned not to use Armorall products years ago. They do shine up the rubber/plastic, but they don't "treat" the material properly. :
Last weekend, I polished my car and taped off the front intake grates with painter's tape. When I removed the tape, a lot of the color came off with it on the passenger side grate!
Is it very difficult to get the grates out to paint them? I am thinking of painting them with everyone's favorite: Plastidip. I wonder if it will have any problem with the heat there.