I've never fitted them to a P6, but I've done front and rear on P5B's, and the fronts were a real pain, and although they looked pretty good they would have taken a lot more fettling than I was prepared to give them to improve things further. The rears were a different matter, and they fitted so well that after one got damaged and I taped over the gouge to tidy things up temporarily the Insurance assessor that inspected it couldn't tell, and paid out for a new steel one....
The one think I would advise if you do fit them is to thickly underseal the backs of them as that lessens the colour difference you get with them and makes them feel more solid.
A lot does depend on who you buy them from.