Spoke with the wife and she said i would be mad, reminded me the rate at which i change my Gti's and said i'd probably have a Mk8 in the summer!!! 
But if you bought the Prets for your current car, they’d fit a mk8 to replace the nasty standard swastika alloys, so IMO it wouldn’t be money wasted.
Also, you’d be preserving the condition of your existing wheels (assuming you’d be keeping them and putting them into storage), so when you put them back on your mk7.5 when the time comes to sell it, a mk7.5 with a set of pristine OEM alloys will be attractive to potential buyers

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