i know someone who is actually a mustang guy, and has several of them, and his 05 LS2 GTO ran something like a 12.85....with an automatic so the missus can drive it...
anyway, as "pony cars" go, i would pick the GTO over the stang, mostly due to the way most of the mustang owners conduct themselves, and keep in mind, i run a forum that has over 25,000 memers..i deal with them every day...and i actually know people who were going to buy a stang, but they wanted to do some research first, so they joined several forums, and after seeing how they were, he wont buy one...also, i like that the GTO stands out a bit...