i have tracey has been tuning my car for years, and i highly doubt he was out abusing a customers car outside of whats necessary. anyway he works for cincy speed now, and i know that would not fly there. like i said ask around cincy and see who has the reputation as the one to stay away from.
and most places wont warranty a t56 past 700ft lbs, i think i saw someone say 800 with the viper output, which will be my next mod. but they say they can handle more just dont warranty them for anymore. as far as how long they hold up all just depends on the amount of abuse you put them though. the only reason my trans from 6speed inc broke was bc my driveshaft came apart and i had been beating the hell out of it for over 2 yrs at 550+ hp