SilentScope
Chemist by profession
I'm with this guy. Although the Mustang isn't quite at the level of the BMW with regards to the quality of materials, it has made quantum leaps in this area and IMO performance is a toss-up.
Close, but is they were "equal", they would be similar price.
The BMW has fit, finish, and quality, as well as technology and design that a mustang cannot match at the moment.
The mustang has made vast improvements, but the M3 has been a pinnacle performance car since the 80's, if not earlier.
