OK, so the next RS6 will be cranking out in excess of 600 horsepower. And we're stressing excess. We've driven tons of hot metal, and can testify that when power output reaches about 500 HP, things get weird. The Shelby GT500 is a blast, but sketchy. The new Viper SRT10 is plain old homicidal. The Z06 is faster than basically anything yet manages to remain fairly compliant — although we've no idea how it's like when you reach the power limit of the big Vette. OK, most current AMG products make around 500 horses but they have several banks of Cray supercomputers keeping your bacon saved. Ferrari's F430 "only" generates 483 HP, yet I'm still in therapy for post-traumatic stress syndrome more than a year later. And I was but a passenger! Can you even imagine a 600+ horse RS6? We're not sure if we're thrilled or frightened. You?