I read about a zillion posts, articles, and testimonials, trying to decide between coilovers and lowering springs. Everyone says something different about coilovers vs lowering springs, and I think it depends on their priorities (ride quality, handling, and looks).
I needed to replace the original OEM shocks anyways, and I wanted the car to keep a nearly-OEM feel because it's my DD. I wanted a slightly lowered look, but not "slammed", and I definitely did not want it to feel like I was on a covered wagon going over railroad tracks all the time. In other words, I wanted to lower it some but not at the expense of ride quality.
In the end I read too many posts here that said "The single worst thing you can do for ride quality is install coilovers." That pushed me over the edge and I went with lowering springs. The ride is about the same as OEM, as best as my uncalibrated butt can tell. I set my KYB AGXs to 1 or 2.