The weak spot in the late model 44 isn't the u-joint or the axle, it's the u-joint caps. They have internal "C" clips that fall off when stressed. With no retainer clips the caps start to walk, you get some play, a cap works out some more, you get play between the cap and the ear, and just like that the ear ovals out and tears. Solution for this is to tack weld the caps to the ears or get aftermarket shafts that allow the use of a full clip. That will prevent 99% of D44 failures. After that the weak spot is the outer axle.

Also something to check out is ARB's new 35 spline D44 locker. It uses the D44 R&P but uses D60 axles and outers (for those that start to get real serious)

Justin