Well the Termi is pushing 10 years old at this point, gotta factor that in. As much as I hate to say it I'd go with the new 5.0 GT. Power is similar, the Cobra isn't exactly light, the interior on the new cars is a bazillion times better, the car itself is smoother/more refined, will still have a warranty most likely etc...
Only thing the Cobra has going for it really is the IRS and the cool factor of having "the Terminator". Also that M112 whine is probably the greatest sound there is...
2000 Mustang GT Steeda #0048 34k miles. 99 Cobra 4V swapped, FTBR IRS swapped, exhaust, tuned by James Gordon.
Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.