My teenage son is about to start driving our old minivan. As I've been looking over the van to make it as safe for him as possible I've realized the headlights are incredibly cloudy. It's almost 20 years old and I've never done any restoration kits on it, so it has 20 years of gunk, grime and UV hazing.

I've thought about just replacing them with new units, but before I do that do any of the headlight restoration stuff actually work? If so I'll give that a try before flat out replacing the entire assembly. If they work what kit should I use?