The only Michelin Pilot Alpins on ebay at present have around 4mm tread. Winters become fairly useless below that in snow and ice so you're paying for old rope.
If you divide the new cost into mm of usable tread (8mm down to 1.6mm - legal limit) then it works out at around £35 per mm. Look at 7mm tread on a tyre and that equates to around £175 (£35 x 5 takes you down to 2mm) worth per tyre so I think that £450 is a cheap amount for almost new tyres.
Rough calculations but you get the idea.
MG
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