Riko, Aberstone has some very old Classic on his various rally stages, he has got the rails to an excellent shine that doesn't seem to tarnish. The room is well heated and ventilated which no doubt helps a bit, but they really are very good.
when I asked him how he did it, he said it was just a wire brush in a dremmel.
Phil, if you are reading, can you add some more detail? Ta.
And regarding getting inox magic juice on your rails in a controlled manner - two drops on the brushes of any old car and run it round for a few laps. Try not to slide the back end out, as this will just run magic potion across the track surface.
Every few months, I wipe my rails clean with a cloth and reapply (only when they start looking a bit dull).