Use brasso, it works really well. Just a note, make sure you don't oversoak the cottonball when doing the plastic side, if you do the plastic may go very slightly matte. The best trick is to rub it for about 5-10 mins on the plastic side with the same cottonball and dip of brasso. The metal part takes a lot longer to remove scratches from with brasso, so if you were in a hurry I'd reccomend autosol. That has very fine spherical abrasive particles in it, and it also works really well. I've got one deep scratch which i couldn't get rid off, but the brasso/autosol combo made my iPod look like new! (I had quite a few scratches too, I think most of the cases are ugly/bulky