I only have the rear Z0K with front poly bushings, the poly up front gave me just a bit more stiffness, I have the HKS coilovers too, so not a very good test bed. According to what SOB said, the rear only Z0K will make the car more neutral (less plowing) add the Z0K front and it will be a bit stiffer and more like stock but stiffer (it will still plow). Every morning I take a 90 degree turn at 30+ no squeel no drift no lean, car just stays flat, I'd take it faster but lots of friendly Leo's around, what can thay say I am not exceeding the speed limit or losing traction. I do not have enough skill to push my car past it's abilities in most cases, I usetacould with the stock setup.