If you want to keep your stock ZSP shocks go with the Eibach Pro Kit springs.
I usually don't recommend stock be paired with aftermarket springs, but I believe the spring rate of the Pro Kit springs and and your ZSP shocks would pair up nicely together as the Pro Kit springs are on the softer side. The old performance dampers which I installed along with the Pro Kit springs are designed to go with the old performance springs which have a spring rate very close to the ZSP shocks found on your car. The only reason I intalled them was because I had non zsp springs before. I will tell you that the ride is LOWER and still very comfortable and compliant.