The rear valance is all black plastic on the stock GTI (not Ed30) and I can now confirm that the GTI's spoiler+exhaust trim is one piece.
According to what colour your GTI is, many owners don't like all that Ford Ka-style black plastic and have painted the upper part - Called the "spoiler" by VW. The lower part is correctly called the "tail pipe trim" and everyone leaves it black. To paint the upper part most people sand it down and use a plasticiser with the paint to give some flex.
If you want to fit an aftermarket exhaust trim OSIR offer a carbonfibre one which is stuck with appropriate adhesive. My CF front mask is stuck on and it stays on!! OSIR's sole European distributor is the TTshop 01234 853 225 (Justin/Dave). Justin is now particularly clued up on various Mk5 bum treatments

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I haven't asked him yet if the OSIR exhaust trim will fit onto a one-piece Ed30 rear.
I hope this helps those who have been asking in a couple of other threads.
