After a bit more research, I am now doubtful they even make a difference on our cars (on track) with the electronic braking system. Which is likely why I can't find many people fitting them. Nothing like the difference it made on my E46 M3, for example.
Not for me, I've always found the brakes in the W211 to be very good.
Then again my mates describe me as more of a white Morgan Freeman with Miss Daisy on board.
I had the hoses off so it was logical to replace at the time with the stainless steel option.