It really just depends on what you want to do with the rig. During a turn, your outside tire has to travel slightly farther than the inside tire, hence why we have diffs to begin with. On 1:1 off-road rigs, you usually have a button, etc to lock the diffs for just this reason. They really help put power down equally to all wheels, but manuverability suffers, so you'll see guys wheeling unlock for tighter turns.
I know on my Wraith and comp rig, I always noticed immediately how much room it took to turn vs. my other rigs. It's because the insisde tires are pushing/plowing the outside tires rather than the diff unlocking and letting it turn tight freely.
