Are locking/unlocking front hubs really needed?

Hi all, Im a new member around here, but been a 4x4 mechanic and driver for a fair few years. Recently iv'e been having a little trouble with my vacuum opp hubs. And Im just curious of weather they are really necessary? Obviously there is the extra rotating mass, though due to the fairly low gearing I cant see that its really going to cause much of a noticeable difference. But is there really going to be that much extra ware on the diff and transfer gubbins?

Does anybody here run fixed front hubs permanently?

Also on a slightly related note, whilst ferreting around my local scrap yard I spotted an old shape Vitara with a decent set of manual locking hubs fitted. Would they be the same fitting as SJ or Jimny parts?

my mate runs permanently locked hubs with no issues

and the vitara hubs should fit fine with a spacer ring on each

as jay said vitara hubs fit with 5mm spacer as do sj fwh's just if you do get them off a vitara don't get the plastic type they are crap

my bro was running his jimny with the vacume hubs perm locked for 2 years with no probs

do you realise that driving a jimny around in 4wd permanently is equivilent to driving a land rover around with diff lock engaged?

Its not in 4wd unless you select it on the t-box mate
The hubs can be locked but still get no drive

Running the axle all the time will cause something to wear out eventually, unlike a LandRover there are no roller bearings supporting the halfshaft or CV.
However, with the mileage that most of us do on the road, I doubt if this will be a problem.