transmission

t-45 has like a 330lb torque rating
t-3650 has a 360lb torgue rating
t-56 has a 450lb torque rating

short story long the t-45 is breakable with too many mods. I can say it has been good to me so far. shifts nice and have no issues to date at 65k. If I get my KB like I want to this summer I am not sure I trust it to live though if I ever ran a sticky tire.