Audi S5 sportback
I'll grab a set in the near future. Still waiting on a used set of Q5 front calipers to pop up on eBay
Those Brembo 4 pots do seem to have disappeared now! Except the 320mm versions!
I did see some B9 S5 calipers, tapered 6 pot for about £500. These would be good as they have the tapered pistons and they are radially mounted, so you can chose your disc size!!