You know where I can find them for cheaper? How long would you say these last?
Like Trannyman said, there's no wear so it'll keep performing its function as long as you don't do something stupid with it. Torsen diffs are what most car manufacturers put in their cars so they have a long service life.
2004 Impala LS - got some mods sold!!!
2009 Subaru Impreza WRX STI
NAIOA moderator Still Imp'n, just in a different Imp.