The new Roush Jackhammer is undoubtedly a fast car, but to me, it doesn't look very much like what I think of when someone says "Mustang". To me, the iconic car that was made in the mid sixties to about 68 is what a Mustang means.
Not that I'd have it towed out of the garage if I found one there. ...

New Roush Mustang looks nice, but not very Mustangish.