I just bought a set of AT's and tried them in the snow recently. Great traction, the rear leafs actually wrapped up on acceleration, something that never happened on the previous cheapmart "all terrains". Wet road driving seems to have improved traction. We are 16" short rain here, so I am curious what a good downpour will do to braking. They will probably be better than the previous, which locked up frequently. Brake slides into the gas station look so stupid.
I bought the AT's because of their reputation for longevity, but I speculate that is done with a hard durometer rubber, which is less capable in the wet - therefore why the AT's may not perform as well. The KO's are supposed to use a dual compound but the Tirerack survey shows the Revo's having better wet traction. Maybe the older AT's are still skewing the curve.
Since you are buying into a new set seriously consider 16" rims as part of the deal, if possible. BFG offers twice the tire sizes in 16", now, and you can keep a shorter sidewall height and lower the unsprung weight, which will help the handling.
I would like to see the results of testing to show which tire has ulitmate traction, and why - variation in tread, compound, aspect ratio, sidewall height, rim size and width, etc. Then we can see if an inch wider tire really has more than a few percentage points of traction, or some "facts" are proven to be counter-intuitive.