The off-road traction of KM2's is excellent, the sidewalls flex very well and they have loads of grip. They are the quietest and smoothest MT I've seen on-road, even quieter and smoother than Toyo MT's.
Mine stood up to lot's of abuse on the rocks and only after a year or so did I start losing some chunks of lugs, and only small pieces at that.
I rotated mine every 2-3k miles and they still have about 50% tread after 30k miles.
However, the tread wore oddly, every other lug on about 1/3 of the inside wore down 1/8-3/16" more than the neighboring lug. This created a very rough ride, even when balanced and with Dyna Beads, to the point that I could no longer run them.
Not exactly sure why they wore like that, but it happened pretty quickly and they went downhill fast.