cheap and easy would be variloks. especially if you got 3.73's already you could just swap the rear.
but then your limited when it comes time for real lockers, if you ever want to go that route.
the aluminium 44 is weaker unless trussed/braced.
Im doing variloks becuase the wife uses the wj as a DD and no way would i trust her with an aussie with a maine winter... my jeep would be in 3 different ditches on the drive home from work.
Paid $500 for a jeep with no engine with quadra drive, sold off a bunch of random stuff that came on the jeep made all but $70 bux back so far. $35 for a varlok axle is pretty damn cheap
not that anyone else will get that lucky but, you never know