If the Passon can stand up to 800 ft/lbs as claimed, that would make it the toughest available. The T56 is tough as hell in the Viper OEM form though. If I was confident with the reputation of the TKO's I might of went that route but i've heard ALOT negatives about them, especially shift quality. Mine fell in my lap almost and was a brand new trans that I paid $1700 for it shipped. It actually was installed in a Drag Pack Chally from Mopar for shipping purposes. Its an expensive swap compared to gathering up parts for a 833 swap for sure, but if your can cut and weld its really a bargain.