Yup and even the SLS got beat by the GT500. The C63 AMG is a fine machine none the less.
Laguna Lap | Mazda Raceway Laguna Seca Fastest Lap Road Tests - Motor Trend Magazine
Just depends on the track man...C63 BS is 2 seconds faster than a 13 GT500 at VIR and GT500 is 6 seconds faster than C63 . The track times will vary since some have longer straight aways than others . You cant go wrong with either car as they both are great cars and bring something different to the table