I’ve only flatted twice on these tires and both were from the shrapnel of snow chains during Portland’s Snowpocolypse 2009. Otherwise, all other flats were from the rim tape shifting and exposing the spoke holes in the rim.
I’ve been using the Schwalbe Marathon XR’s on my touring bicycle for the majority of the time over the last year or so. I’m very pleased with their reliability, traction, durability and long long lasting tread wear. Over 4,000 miles on my current set and they still look awesome.
The real downfall of these tires is their weight and rolling resistance. I constantly keep them at the top PSI and have to keep checking the brakes to make sure they aren’t rubbing because these tank treads make one feel so very, VERY slow.
I’m at the point where I’m switching back to a smaller, faster, albeit less reliable tire to get around town and go on some long trips. Sometimes, the extra work isn’t worth the extra protection.
Think of it as steel-toed boots. Walk through anything, but would you really want to run in them?