What you should get is depends on your pocket and on type of wheeling you doing.

Rocks/Mud/Deep snow + - you might consider M/T as they would be better, b/c they got

Sand/Streets - you better off with A/T, as agressive thread is your foe then

And remember that M/T wears off faster 8)

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as of what i am running - Dayton Timberline M/T - not the cheapest, but they are handling quite nice so far with rocks and occasional mud.