I've had mixed results with a variety of products. It really depends on the damage you're trying to repair. Beyond wax, I imagine they all use some sort of abrasive. From extremely fine polishing compound to fine wet/dry sandpaper.
Most OEM light assemblies I've messed with have some of clear coating on the actual plastic lens. I'd guess some sort of acrylic coating. If this is damaged, the process is to abrade it off and actually polish the bare lens, which works fine but at this point the protective coating is gone and will require more frequent preventative maintenance. Kinda like wax on the paint. It's a two edged sword, for sure. UV is hard on everything, some things deteriorate faster.
It occurs to me that aftermarket assemblies likely do away with such coatings as a cost saving measure. I've used them with success, but don't kid myself about them being the same as OEM at half the cost or less.
Perhaps that's all TMI. Photos of what you're working with may be helpful.
