Yeah, wore 7-8mm of tread in 9 days driving on dirt roads. You could actually see the diference in the tread depth from looking at it in the morning, then looking at it at the end of the day!!!!!
265/70/16 still gives you the width but is that little bit less height, so you will get back some economy and power. I'm happy with my 31/10.5/15's but you would need to change rims, plus make sure you have enough lift/clearance to run them, I'm more than happy for anyone to test fit mine to see if they will fit.
Fros, has those Hankook MT's 265/70/16's they look really impressive.
I also think I know where a set of 4 255/70/16 BF Goodrich AT's are with 8mm of tread on em for somewhere like 300 - 400 bucks... If that helps get you by.