IRS, a kicking V8 and Ecoboost powerplant, I like the looks, improved interior, better handling....personally I cannot wait to try one of these out. I remember driving a Terminator Cobra a few years ago and that car was absolutely amazing, I think this will be even better.
I have always said that Mustangs are big, heavy, poorly handling cars.
...then I kept renting them while in California/Hawaii and quite frankly, I really like them. Outward visibility/parking is not as easy as in a Subaru, but it's not impossible.
I always found the base V6 to be a great engine with plenty of power and reasonable fuel economy (so long as you're not always in stop n' go traffic).
If this thing finally handles well, has an engine that will have a better weight balance and more power (maybe more efficient?), then I don't see how it's such a 'failure'.
Personally, a Mustang is a convertible or bust, though...but that angers me because the convertible with the 2.3T is only available in 'premium' trim, meaning $7,500 more than the base V6 convertible, and after tax and other forced options, it's $46k instead of $35k if you only want the 2.3T.
Honestly, the base convertible still seems like the best value to me.