I've been happy with my MT KM2 choise so far, but only have about 150 miles on them. Since I will also drive street most often, I siped ONLY the center lugs to help water displacement. Ride is MUCH better then my bias (obviously), and were actually quieter then expected. I would have went with the AT, but my size choise was not availible in AT's, only MT's.
Tires selection is personal depending on specific rig, your purpose, and even the terrain/location that's specific to you. Still some brands are better then others.