Advantage?

I previously posted about purchasing the KYB AGX Gas Shocks. I'm planning on getting those unless the Yellow's show up soon for way cheap. But then people recommended getting the GC coilovers. Whats the advantage of getting those instead of just springs. With the coilovers, especially the GC's does it make adjusting my ride much easier. Also if i go with the KYB and GC setup if the GC's lower to 3.5" and i assume the shock itself can adjust, which one will i be adjusting and when to adjust it? Any bad experiences on groupbuy. First purchase for this stock EX....just a kid paranoid as hell