I talked to the Cobra Jet engineers when I was at Watson Racing and they use a C3 prepared by Joel's on Joy a local race trans shop in MI. They chose it because of one main reason...quick access to replacement parts. When you are racing at the level the CJ's race on, you are generally checking/replacing/modifying parts on the car all the time and need quick access to parts. I'd venture to say most transmissions in 6-9sec cars (in the 1/4 mile) are autos of some sort due to consistency and needing two hands on the wheel
