A word of warning, colour coding the existing side skirts has been proven difficult to get right without subsequent flaking and peeling.
A fair comment, but not entirely justified.
Yes, I've suffered with paint peeling from my standard GTI colour coded skirts. However, that was down to the complete and utter incompetence of the stealer, by not using ANY primer, nor clear coat. With any plastics, including bumpers and side skirts, you must use a specialist flexible "plastic" primer, before the colour coat and clear coats.
For the record, I've not had any peeling or flaking from my colour-coded front and rear bumpers, which are subjected to more flexing than the side skirts.
It is much better to get the R32 side skirts and paint them instead as they are smooth rather than the GTI's which has a rough moulding to it.
If you must have a flat finish, then the R32 skirts are the way to go. However, if you don't mind the grained look, just like the lower half of the rear bumper, and front lip, then it is perfectly OK to colour code them, providing the correct flexy primer is used.
One problem with removing the original skirts, is that they are "bonded" to the metalwork with a specialist adhesive. This needs specialist tools to cut the adhesive, and strong specialist solvents to remove the residue. Obviously, a professional bodyshop, as well as windscreen fitters, should have these.