I just installed the GC street plates on my KW V3s.
http://www.ground-control-store.com/.../II=886/CA=287
So here are my impressions:
First of all I wanted/needed a setup that fits stock sized springs. These do.
Also, I absolutely want to retain a quiet and comfy ride. Those plates don't use a spherical "race" bearing, and you also reuse the stock rubber spring pad. GC assured me the plates are quiet and they are.
Added bonus, from what I can tell (someone correct me if I'm wrong) the bearing insert is oem which means it's cheap/easy to replace if they ever go bad.
I did have an issue however, one stud broke as I was tightening it. It wasn't even tight yet, it just snapped. I called GC and they sent replacement parts right away. Great customer service.
I might be going off topic by now but GC picks up the phone every time. I couldn't get someone to pick up at TC Kline if my life depended on it.
Anyways, very happy with my GC plates so far.