Just a minor point... 'wheel base' is used to describe the distance between the front and rear axle and 'wheel track' is for the distance between wheels on the same axle. Clearly your question is referring to wheel track, but thought you might like to know
In theory, a wider track will improve stability around the roll axis and reduce the chance of a roll over, but in practice a couple of inches makes very little measurable difference.
However, the main advantage to wheels sticking out a bit is the much improved mud spray you get all down the side of your rig after a day on the trails. That really shows others you're a carefree reckless hardcore wheeler and are not to be messed with.