well, considering dana 44 uses a 5-297x u-joint, they are the same size joint as any later year cherokee with the dana 30, and older xj's with anti-lock brakes.
you can upgrade the joints to 5-760x to gain a little more strength. but going with chromo shafts and utm joints will get you up to about d60 strength.
but you want a weak link in there, u-joints are easier to pack along with you than shafts. that's if you're lucky enough not to take out the ears when the joint snaps.
i know a guy that ran 39.5 pit bulls on his chromo d44 tj rubi axles for a few years. and he wheels the tough trails. now he has d60 rock crusher/custom 609 axles on 35x9.5 boggers.
either way, he hasn't even had to replace a u-joint.
1990 xj 8 inch Staang's Fab long arms
1999 xj. current daily driver
2000 xj 4.5 inch rubicon express, 33 timberlines
1997 tj 2 inch bb, 33 mtr, trailhead customs tube fenders, titan 10k winch
1999 tj 2 inch bb, 2 inch bl, 33 mtr
I get mine from TMR Customs