The problem was with the T1-S was the shoulder of the tyre was breaking away from the tyre itself, thus casuing the unpredictable handling etc.

Toyo re-released the tyre as the T1-R and subsquently put two symetrical bands around the egdes of the tyre to stop the same thing happening, and solving the problem

I had a very early set of Toyo T1-S's and they were spot on, excellent grip in the dry and wet and the shoulders were fine, I think the problme must have been with later tyres.

IIRC the first T1-S's came standard on the Evo 6!?