Hi Ben
I had the first 2 on my GTI PP, it went to the dealers 3 times and they failed to find a solution, so I gave up. The rattle was the worst, i was convinced it was coming from the a-pillar but they couldnt find it. It started off as occasional but ended up being pretty constant. The metallic ringing was there but didnt bother me.
Car has now been replaced with an R, which also rattles like hell !