I've gone through a few sets of tires on my 21 AT Std. and found I'm tied between the Mitas E07+ and the Shinko 804/805 combo. I really liked the Mitas (on the rear) but got only about 4k out of it. The Shinkos are going to surpass that mileage mark by a long shot.
In the dirt, the winner is Shinko, unless I'm side-hilling or it's really muddy. The Mitas rear was good in the dirt, but the front was a crap shoot on every ride. I never found the right combination of pressure and body position to make it stick (dirt or tarmac).
On the tarmac, the Mitas (rear) was very good and surprisingly quiet. The Shinkos are just a tad louder but - and this surprised me - they have more stiction than the Mitas despite the knobbier tread. I just finished a 700 mile ride through the Texas Hill Country, including the Three Twisted Sisters, on a fresh set of Shinkos and never had the guys on street tires have to wait for me.
All said, I wanted the Motoz Adventure on the rear and the TKC80 on the front, but neither tire was available. Maybe on the next set.