It all depends on how extreme you want to go. How low is too low? How stiff is too stiff? I am running H&R springs, Koni adjustable shocks and struts, iPd anti-roll bars, Powerflex polyurethane bushings. I liked the H&R's because they are progressive, while also giving me the drop and handling I was looking for, with a very livable stiffness. I liked the Koni's because they are just as good as any other shock/strut out there, but are adjustable. I didn't have much choice with the iPd anti-roll bars, but boy oh boy are they nice. The poly bushings did wonders for initial turn in, and quick changes in steering angle.

To get a better description of the setup I'm running, check the archives. I did an entire review on my suspension shortly after modifying it.