Best Transfer Case

hi all..... i don't know if it's a repost, if so my apologies.

i own a 1992 Defender (110) with the V8-3.5 engine. recently i bought a 1990 Range Classic with the V8-3.9 engine, so both engine and automatic gearbox are now in the Defender.

my question is, should i keep the original transfer case with the new engine and the auto trans, or should i change it with the rangie's??

and i don't mean about cruising.. i assume that in highways would be more comfortable with the rangie's transfer.

what i'm intresting is about hard offroading, low ranges and central diff locking (auto-manual). What will i get and what will i lose with one or another?

p.s. i run on 35's

defender transfer box will be a 1.410 unless some one changed it ,so with 3.9 auto a 1.222 box would be better or the borg warner that came with auto ,but you need rr front prop and box mounts borg warner will have no diff lock but has viscous which does same thing and gives advantage off diff lock without having to put it in or out perfect for mixed conditions on road ,ive fitted quite a few if you want more info

so you suggest better rr for offroading right?

depends on your off roading 2 x maxi drive diffs would be good ,but in that borg warner supplies drive to both axles without having to engage/disengage a diff lock and still be able to turn while doing in so i would think so for most people,