Can you really compare kralwers and mtrs though?  Wouldnn't you want to compare km2 sidewalls to mtr sidewalls? 

I wish we sold more mud tires at the shop, for no other reasons than to get good feedback and to see what comes in with sidewalls failures.  In 10 months at the shop, I've only seen sidewalls on any tires fail due to being run flat or at too low pressure, or due to age degradation.