Another Marathon Plus user, if your looking for flat free and durability get these tires. At a Schwalbe booth this summer, I had a chance to see a cross section of the Marathon Plus tire, it is solidly built and I decided to give them a try. I've got just over 1,300 commuting miles on Marathon Plus and I really like these tires. They do not show any sign of wear and seem like they will last forever.

My commute is a mix of gravel, mup and city streets. The street portion is only a couple of miles but it is in an industrial area and there is debris (glass, wire, wood, railroad tracks) every day and the tires are holding up extremely well compared to others I have used. When the time comes to replace them (likely at least another 2-3k miles) I'm going to be getting the same tires.