Just put them on the rear of my 99 A4 2.8Q, reused the original sport suspension springs.

Everything's torqued to specs, but I'm noticing knocking noises when I go over bumps, especially at low speeds. The noises weren't there before, so I'm assuming its something to do with the new suspension setup.

I'm curious if anyone else has had similar problems...

Sometimes the Bilstein bushings run a little more narrow than stock. If you tighten that top bolt real tight, you can pinch the housing metal in tighter against the bushing and help eliminate that noise.

I torqued the snot out of the upper shock bolt, and everything's nice and quiet now. Thanks for the tip Mike!