you know, this is a very valid question! If you ask orthodox four wheelers like myself I am all for stick shift, manual hubs and diff locks... A traditionalist always would agree that with more driver control (given that the driver deserves the extra control) is always the better way to go. However, I do remember watching a Top Gear episode on extreme 4x4 machines in Iceland (the best 4x4 by far I have seen) and they were all auto for a good reason... It seemed that with their mechanically aligned limited slips, it was more efficient for the machines to be automatic so that they would tread carefully and not dig holes under their tires as manual transmissions allow a novice driver to burn....
So, guys the answer to this in my view is dependant on how sensitive you are both to your vehicle's output as well as the particular soil you want to tread on...
A safety measure therefore has been to use an auto tranny in difficult conditions so that driver error can be minimized...
For me however, having rocked GMC suburbans out of the empty quarter in Saudi Arabia at the ripe at of 11 and having fished for rocks in an suzuki FX while acending a mud incline, an auto box insults both my intelligence and my experience...
But for each his own I guess....................