Hey, I'd say that's a good question!

I've used wax before on smooth plastic surfaces and always had good results. However, I think a shiny finish is contrary to the existence of the the hood insert (it's supposed to be an anti-glare feature.) Mine is a little shabby so I plan on repainting it so it's closer to being a matte-finish.

I hope you wait to hear from someone who has a VX that's more "like new" before you try waxing.