I not only run them until smooth I usually run them until I see nylon and even at that I only got about 13,000 out of my Metz Marathon.20,000 on the front metz Laertech (I think it's Lasertech without looking)and still have tread left.

I learned all I need to know about life by killing smart people and eating their brains.
Eat right ,Exercise ,Stay fit, Die Anyway!