Had my first flat on my new Schwalbe Marathon Supremes on the ride in this morning. I only have about 40 miles on these tires and love them. I was pretty upset when i felt the rear tire bog down and i knew it was flat. Well, Im going to write this off as bad luck. I cant hold it against the tire. It was a 1" long razer sharp nail slammed straight into the tread. How it picked this evil looking spike up is beyond me. I took some ribbing at work because co workers knew i just spent $120 on "flat resistant" tires and i walked up with a flat tire. it happened within a quarter mile of work.