Go ahead and make the jump to an M3 LSD, If you break that, your doing something wrong.
5000 rpm launches are hard on EVERYTHING. Engine, clutch, transmission, axle, diff, transaxles, U-joints, guibo....
What do you mean... "break"? in LSD's, the clutches wear out if your drifting\burning out all the time, so if that's what your talking about then just get new clutchpacks.