Kinked beads

[Grumpy Goat]

I'm not sure I quite get this. The calipers are a single hydraulic circuit. When you apply pressure all the pistons push equally. Any off center of the mount should be of no consequence.

I agree. I would expect that slightly tapered wear (along the length of the pad) comes because the calipers are floating and the bottom end of the pads would tend to see the disk first and the top end last. With more pistons, this tendency for imbalance would decrease as the clamping load is more spread out.

Having said that, pads can wear differently side to side within the caliper, i.e. the outer pad vs the inner pad, if the caliper is fixed slightly off-center w.r.t the disk. That is what applying pressure while torquing the caliper bolts is intending to minimize.

I just did a brake service on the RS yesterday, replacing the front pads. The video, which might be useful to some, is here. I have close-up photos of the pads front and rear.