I own 2 pair of MTB shoes, both Shimano.

One is an "all terrain" shoe that I got when I first got into MTB.

the other has a carbon-fiber reinforced sole - SHM225S. I've been wearing these for 3 years (I think)...they're pretty ragged now but have held up rather well.

I haven't had any problems with either pair...but...that doesn't mean I haven't been looking for a new pair...OOOO! Somethin shiney!