I'm running Koni Adjustables with the Eibach Prokit, and, honestly, I can't fathom how anyone could drive anything much lower. I dunno, maybe I got rooked, but I can't even slide my low profile floor jack (maybe 3" high?) under the oil pan now and the back wheels are right up in the wheel wells. AND, it's about as firm/stiff as I would want it having to drive on real roads.