Another factor is where you source your D44 from. Not all 44's are created equal.
example ... the much vaunted Rubicon has a D44 front ... but in reality it is the smallest lightest carrier and has D30 outers. Very compromised design.
Get a waggy D44 and it is a good middle ground D44 And depending on the year (older 70's model are better) you can put the heavy carrier inside so gear choice isnt a a big problem. 5.38's should be fine just don't slap a big block in it lol
Or you can have a D44 like the one in my trooper ... came out of a mid 70's Chevy one ton. Has the big carrier, heavier outers, thinker axles etc etc, and has a beefy ring and pinion, not to mention very roomy for a big locker
It costs a few bucks more to set it up right, but so far it has been bullit proof.
REally reading up on all the varients of the D44 and then deciding will help a whole bunch
Oh and I run 5.38 in my axle with mechanical lockers (detroit) and they work great. no problem and I've run them about 5 years now I think. I run 37 inch tires and a double reduction transfer case so i can put some torque down at low speeds and they gears always look perfect when I service it.
currently seeking my next isuzu-stein to be ... LOL