4D0413031AQ is for the PF 2.8 sport so will have quite a different weight profile to an FL S8. I would be disinclined to fit those to an S8 tbh as it may end up under-damped.
The best dampers currently available for the D2 are the Bilstein B6, but they are a tad spendy at 150 a corner. Very much worth it if you enjoy a 'spirited' drive from time to time though
Ainars - I'm pretty sure you are correct there. I can't remember the exact differences tbh as I don't see many PFs so I'd need a set side by side to remind me.