I have them on my ride. Here're the cons:

Expensive

heard many people said they make noise, but never heard a thing on mine. May be my exhaust is too loud

Have to reset shock's damping at stock height to release its "stiffness" , GC coil get stiff over time. So after had them on like almost a yr, I had to reset to stock height with my Tokico Illuminas shocks been riding around like stock for 2 weeks. Now waiting for my camber kit to come it for lower drop, but the ride now is like brand new.