The caliper on the FL car is the same as the PFL but I would not recommend fitting Redstuff to an RS3.
I had a bad experience with the Redstuff pads on my PFL car (they glazed and overheated the Alcon disc upgrade I had fitted) and replaced them with Ferodo DS Performance or Ferodo Premier pads (I tried both and they were way better than Redstuff).
I was at a track day at Castle Coombe in the UK last year (Audi Driver International event) where two RS3's were running Redstuff pads with stock discs. Both cars ****** their pads, overheated the discs and boiled the brake fluid after 4 or 5 laps. The same two cars attended this years event at the same track but had new discs but with Ferodo pads (one with DS2500) and had no brake problems this time.
You will find people on various forums who have used the Redstuff with no issues but try finding a leading tuning company who will recommend fitting Redstuff pads as an upgrade on an RS3.
My FL car is running 500+ bhp and so I have again upgraded the stock discs and pads (see pic below). The Revo/Alcon discs do not fit the FL car (alloy bell housing is different offset - Revo are apparently working on this) so I have opted to have some two piece floating 380mm x 34mm grooved and directional vane discs made. Currently running them with the Ferodo DS Performance pads but will shortly be swapping them for the DS2500 pads.
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