Wow, I forgot about this thread. Boy have I gone off the reservation from what I was recommended to do here over 3 years ago!
Sbutcher2, I'm not sure how the splitter affected your handling, but that's beside the point. I don't advise changing only the rear springs to Z0K, as that will drop the rear and leave the front at stock ride height. If anything, go with coilovers all around or Z0K springs all around.