Did that today on the C6Z and this is the first time it's been done since I bought the car a year ago. I could feel a dramatic difference on the surfaces after the clay bar process was done. Feels very silky smooth to the touch, looks REAL pretty too, and I don't even have any finish layer on it yet. Of course, it's a back breaker getting down low to do those rocker panels.
But DEFINITELY worth doing!