Looks like they last pretty good from what righthooker says so look a bloody good buy.
I will use my normal road tyres[toyo T1-R's] when on track as i cant afford another set of 17's at the min and my 15's wont go over brakes.
If not got enough cash for rear beam[like me at the min] then the shims are supposed to be better than nothing. Thats what i will be putting on min for donno on 29th.