replacement will be a non VW branded item (but identical) unless you stipulate a VW item is used
(which may take longer to get and cost you personally more )
depends how picky you are
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i had a generic one fitted and its identical (bar the branding name).
Like others have said, your biggest concern should be the experience of the fitter.
Ask them is theyve done a mk5 before and any tips
(fwiw mine removed a strip from the bottom and cut edges off some sealing strips, i was having kittens until he explained why he was doing it
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)
also be aware of misty windows after fitment, as that could indicate a leaking screen
hth
john