My MKIII in racing blue had black roof rails and black trims around the windows and I put a black protector on the bumper for loading/unloading and it fitted in well.

 

My petrol blue MKIV has silver rails and trim so initially thought I'd get a silver one this time but now I'm not so sure if it'll look right.

Has anyone photos of their cars with either?

I had silver vRS wagon and went black bumper protection. Blended perfectly, particularly as has black badging - will post a picture tonight 

I went with clear one (clear PPF foil) on my Steel Grey Estate.