mr077,
I run the Toyo Proxy S/T LT tire. They last a long time (if you don't run over a curb or anything) and are very stable. The breakaway is controlled and predictable even though the sideload adheasion limit is not very high. Braking is very good, even in the wet. They are very comfortable high speed cruising tires. I expect the MT's to be similar. So much depends on rubber compound, though. The real test will be the first autocross after I get them on my car.
I've ran several set of bias ply MT Competitor Series tires on my Cobra. They were very sticky and gave tremendous traction because the rubber compound was so soft. A set would last a year, if I was lucky.
Paul