None as of yet! but here in central France its very rare for the roads to be salted in winter. To do it properly would need all the plastic panels to be removed , the car being lifted , whether the expense and hassle is worth it , is your choice.
My main areas of concern are the bottom of the doors ( hidden by the plastic side panels ) and the inner and cill bottoms . There are two plastic bungs under the cills near the jacking points which when removed and a torch shone up reveal that there is a thin film of wettish / oily factory protection sprayed inside the inner cills . How long its longevity , is anyone's answer ?
I seem to remember photos of a very early model ( might be a different forum ) of rust like discoloration of the spot welds under the paint along the seams of the cill bottoms under the car , before ordering mine I mentioned this to the dealer who dismissed it as " forum nonsense " and I should not believe amateurish ill informed people ( customers ) from clouding my judgement and stick to the officially stated advertising blurb.
Even if this was the case , this is within the structure and any additional rust proofing would just be an external covering which would hide the evidence for another day ? Tricky, common sense says " do it " what harm can it do, against expense and kicking the can down the road until whatever paint/corrosion warranty has expired.
