hi
gotta say something about this !
i have the 500 and am still waiting for my 08 orange(stuck in a train yard in cleveland !!!!)
i also have a saleen parnelli jones and a saleen extreme, just to mention a few.
i love the looks of the 500, but its a pig. my saleens out run it and run rings around it. it handles like garbage, sits way to high, loose suspension, the clutch is a joke, its exhaust sucks, and the fit and finish suck, and unless you do some performance mods, it will be a major disappointment to you
before my mods, she was 428 at the rear wheels(now dyno 615 rwhp).
the only benefit is that it has the looks and appeal and the day that old guy dies, anything that has shelby on it will be collectible(if i live that longlol)
can't compare it to the challenger yet(still waiting), but from what i've heard a few mods will make the challenger a force to be reckoned with(especially next years manual trans)
just my opinions

sam
#8h289474 (still freakin waiting)
and psthe chassis on the stang is new since 05 "