Actually the discs I have are cast iron and do have the 'rusting' properties that you describe, coating the forks and the front of the bike with a difficult to remove reddish stain.......I am heartily sick of them, irrespective of the superior 'in the wet' stopping power. They are also heavy.
They might not be much of a problem in sunny Australia, but in 'Old Blighty', where it is either raining or about to rain, it gets to be a bind ..... after a while.
They are 'buggered' either way. Motorworks do EBC's at £140 a pop, plus the pads. Might have to plump for those if nothing else pops up locally.
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