Just as an FYI - Phaeton discs are an option, They are Brembo also just without the drilled holes. The part number is 3D0615301N
My RS4 had 26k miles on it when I bought it. Drove perfectly for 3 months and then I started to feel a tremor through the steering wheel when braking at all speeds down to 40mph.
My buddy also bought an RS4 same time as myself and the same thing happened to him but his tremors were much worse than mine.
He bought new RS4 discs big bucks and I got mine skimmed.
My skimmed discs lasted 3 months and I felt the tremor return again.
We both live and work in town so we both do a lot of short stop driving.
I've read that the drilled discs don't cope well with this type of driving.
(I do blow out the carbon at weekends)
So I bought the Phaeton discs and swapped over the bells last week, just 400 euro all in for both.
I couldn't justify the cost of new drilled discs and then have to wait and see how long before the issue returns.
I've spoken to another RS4 owner here in Ireland and he went through 3 sets of Audi drilled discs in one year. Each replaced under warranty.
Original Phaeton Disc
Bolts removal
Bell removed from Phaeton Disc
Bell removed from RS4 Disc
Phaeton Disc with RS4 Bell ready to refit