they say a picture is worth a thousand words so look at the difference in the pads. the CTS-V brakes have almost twice the surface area as the ss brakes. not to mention that there are staggered sizes in the pistons of the V developed by GM to stop a heavy car. i melted the stock ss setup at VIR in two days.
the top pad is a hawk HP plus SS and the bottom is a hawk DTC 30 CTS-V.