If you go to
www.tirerack.com and look up the tires you are interested in, they have comparisons and a bunch of consumer reviews.
The MTR is actually better compared with the BFG Mud Terrain KM, as they are both mud tires.
I've done alot of research on the MTR's, as I'm planning on getting a set for my Jeep.
From what I've read, the MTR's are great on the rocks, good onroad (for a mud tire, that is), good in snow, and good in the rain.
They also tend to wear quickly (less than 30k) and get louder as they wear.
The BFG AT's are great onroad, and pretty good offroad, except for mud.They also last much longer than the MTR's especially on heavy vehicles. 40-50K out of them is pretty normal.
If you drive on alot of packed snow, the BFG's will be much better.
As far as tires go, for packed snow, you want an AT, for deep, loose snow, you want a MT.
Bottom line is that the BFG AT is a great street tire that is also pretty good in most conditions offraod.
The MTR is a great offroad tire that is still liveable on the street.
You need to decide where your priorities lay:
offroad performance, or street performance?
You can't have both, so one has to come at the expense of the other.
Hope that helps answer your question.