You think comparing an S2000 and comparing a Terminator is apples and oranges, but you want to compare a gutted 400hp S2000 to what I'm guessing are stock non-terminator mustangs?
The Cobra has a 3.55 with a 6 speed, it's not hurting gear wise.
And sadly, I agree... and facts agree with xxbckiexx. Z06 > S2000/cobra