The Yokohama AVSs are my current street/summer tire favorite.

MrTews drove on them for 2 years, drove them from Arizona to Michigan. He gave them to me, and I rode on them for a few months before driving the Alcan to Alaska (much high speed gravel and tight corners). I took them across the Denali Highway (all gravel and fist-sized boulders) and up to the the foot of the Gulkhana glacier (big, wet granite rock).
They performed flawlessly on all the terrain that I encountered, even providing decent flotation in some very loose pea-gravel found in a gravel pit.

My only complaint was the tendency to wander into ruts in poor roads. I think that a wider wheel (than stock) would cut down on this. I finally retired them a month ago, deciding to switch to some Nokian Hakkapellita SUV studs for winter.

My next set of summer tires will most definately be the AVSs again, though maybe in a 16 or 17" size.