About 10 years ago or so the factory five cobra was junk. The worst one made.
I was planning to build one and did my homework. I have a book at home called the complete guide to cobra replicas (1st or second edition) and they had an entire chapter pointing out how poorly the factory five car was built and designed. They're on the 4th edition of that book now.
http://www.cobracountry.com/cobrabk.html
There used to be a place in Orange called cobra City, it was a used car dealer than only sold cobras (real and replicas). They absolutely bagged on the FF, saying it was a plastic mustang II. I spent allot of time there and drove at least 10 different cobras.
But having said alll that, FF is building some pretty nice looking GT40s and daytona coupes nowadays and I've been told that their cobra is much better than it used to be. The new FF cobra now uses most of the parts from a 86-95 mustang and is the least expensive way to go.
Superformance makes the very best cobra but they are 5 times the cost of a factory five.