Yeah, I was fortunate enough to test tires in winter, controlled conditions, closed course, etc. Winter tires made the autocross course in about 32 sec, and the best anyone could do on all-seasons was around 45 (OK, one instructor had an insane run at 42.5). Doesn't sound like much, but that's a FIFTY percent increase - fully half again logner! The comparative lack of control on the all-seasons was unbelievable, noticable even to the most novice driver there. Summer tires (tyres, sorry!) couldn't complete the course in under 1:10 and, in one case, couldn't compelte the course at all - and it was a LEVEL course!