I say CTS-V!! Coupe, Sedan or Wagon.
CTS-V = 556HP :biggrin::biggrin:
AMG E63 = 518 HP :frown:
Lexus IS-F = 416 HP :frown::frown:
surely your not evaluating the greatness of a car on how much HP it has...:frown::frown::frown: (triple frown to trump your double frown of the ISF)