Mine has B8s fitted and I don't think they're that great tbh - the car is firmer but body control is only marginally better than SACHS Advantage which are quite cheap in comparison . The problem with the A3's damping is the front and it appears aftermarket dampers follow the same damping profile of lots of bump and low rebound damping. The rears are fine (B8s nicely composed, but standard Sport dampers are ok too). But the front dampers are all too stiff on bump IMO, which feels like riding a pogo stick, so the ride is stiff and doesn't like to compress but when it does it rebounds/extends too quickly and the front end lifts/jumps too much.
There's a dip/sunken road new me and with the B8s it's better than before but not a patch on my BMW (also fitted with B8 dampers), the A3 jumps up in reaction where the BMW stays sucked to the road in comparison.
I would say FSD sound like a good bet.