Sorry to be vague, I didn't mean that the slicks last longer than the SKs, but that if you use the SKs on the road primarily that you will wear down the knobs pretty quickly. The slicks and the SKs lasted just about the same amount of mileage for me. They are definitely strong and unlikely to fail or flat in my experience, not sure where you are hearing about the slicks' reputation. They are tanks compared to my Rene Herse slicks.