I’ve had 4x4 vehicles before and am aware of the limitations of open diffs.
If I get a van I would not splurge for 4x4; the cost is too high. But a locking diff would be a good alternative for the kind of forest road meandering I am planning. Apparently the GMC option code is G80 and is listing on the tag in the glove box. Demos of this diff in soft ground are impressive.
If I get a pickup (see upcoming blog post) 4x4 isn’t as great a \($ bump but a locker would likely still be cheaper, less maintenance and\)$.