I have been using the "bad" Stage Right brake for over 5 years and cannot attribute any trans failures to it.......I generally just wear out clutches (of course most of the stuff you can break has been upgraded)
I have about 40-50 nothing higher than 15 or so on mine and hasn't skipped a beat yet This is on a street/strip build from PTS and I put the brake in. $110 for the kit.