I wanted to get my brother a coilover kit for his 335xi and I wanted to get some real world feedback on what people are running.

He does autocross and track events with me, and being in NYC means horrible roads, what provides a good mix of everyday usability but also is stiff enough for some track time?

I think its between the Bilstein PSS9s and the KW Variant2.

For the PSS9 and the adjustable dampening, how do you adjust the dampening of the rear?