My experience with the 3M kit was fantastic. I got the kit that came with 3 or 4 different grits of sandpaper pads, a drill attachment, polishing pad and polishing compound. My original lights started to get yellowed and hazy to a point where you could not see the inside of the light anymore. One of my headlights got replaced after a fender-bender and I was left with two very different headlights.
Though I was skeptical, I bought the kit since I knew I needed to sand the lens down and it was the only one at the store with sand paper included.
It took about one hour to restore my old headlight. The first heavy grit sandpaper was scary to use... it is really counter-intuitive!!! I thought, "oh no what have I done?"... But in the end I was amazed at the way it looked. It was not 100% exactly like the new one but it came pretty damn close. My family members were not able to tell one from the other. I could tell that the restored lens was a bit less "crystally" (if that makes sense) but you really had to look hard to see the difference.
I ditched the drill-gun early in the process and did it by hand since I felt I had better control. It really was pretty easy!
It has been over a year and I have not polished either since I performed the restoration. Tommorow, if I find my camera, I will start a new thread and post pics of the headlights after a year of weather. If I can do it, anybody can.
Sorry it didn't work for you 1stE53
This is what I bought:
Amazon.com: 3M Headlight Lens Restoration System: Automotive: Reviews, Prices & more
Rui