I've ran with all kinda of rigs on all kinds of trails...
If you're planing on doing a LOT of DEEP mud - go with the M/T. Otherwise, on a DD, the A/T's are going to be quieter, longer lasting, and often BETTER traction. The A/T's have spanked the M/T's on our snow / ice runs, and kept up just fine on rocks & most trails... and RULE in the sand. The M/T's hook up better in mud, but the A/T's keep up just fine in all but the deepest / thickest of mud. The guys I've ran with praise the on-road characteristics of the A/T.
That said, I've heard the MT's have been re-designed to have more siphing which should help them hook up in cold weather trails... but I have not verified that. I went with 29" Pep-Boys Dakota M/T's for about $110 a tire installed with warranty. I've been extremely happy with them. The BFG A/T's out-perform me in snow & ice, but not by too much... and I've never got stuck in Snow / Ice yet... I just slide a bit more when the A/T's remain fully planted.