As with any other spring install, if you buy only the GC kit and install it on stock struts you'll have to do the entire process a 2nd time when you want thos Konis in there. This is what I did because I didn't know if I was gonna keep the GCs and didn't want to ruin a brand new set of Konis. Now that I'm happy with the GC kit I have to go back and install it on Konis... Again I have access to lift and air tools so everything's easier.
Then there's the problem of bounciness. Even good SVT shocks don't have the rebound damping necessary to control the ERS springs in the GC kit. This will show mostly at highway speeds if you hit a swoopy dip in the road it'll take the car a 2nd bounce before it takes a set. This is NOT a really sought after behaviour and the only way to avoid it is with a stiffer shock valving (aka Konis or other). I've been living with it for a while though and although I swear at it every time I can't help but smile whenever I step out of my car and take a good look at it
My next upgrade is Konis with sway bars, strut bars and better bushings all around.
