I'm not disagreeing for the sake of disagreement, but I tried two different "polishing" kits and they are not worth the time and effort IMO. If the lenses are pretty yellow and oxidized (like mine were and like practically every 240 I see), then you are spending a couple of hours rubbing different grades of sandpaper (or 3m buffing wheels or whatever else people have concocted) over your lenses for what I felt were only moderate results. In terms of plastic lens replacement - I don't think any one here would deny that nothing is going to beat new (whether aftermarket reproduction or Volvo/Cibie) lenses for your head lamps. Whatever your willing to spend ($60-$200) for the pieces will make your 240 look great again and you'll be glad you did it. It makes a dramatic difference.
~jason