I've broken 3 Campagnolo Nuovo Record cranks and one TA Cyclotouriste crank. All four broke at the pedal hole, not at the thick arm location like MEV's. 2 breakages were on tour, 2 were close to home on day rides. Each was during a hill climb without warning resulting in a near crash due to sudden unexpected loss of pedal support. I've never broken a Shimano XT MTB crank, so yes the beefier construction solved the problem for me.
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