In reply to Thomas Hardbattle:
Which ones? They make different soles with different compounds for different environments. The mont compound is designed for high altitude but uses a stiffer compound, its tough but not as grippy but won't deform as much and is more suited to strapping crampons to. The megagrip compound is as it sounds, trail running in the wet, mountain biking etc.
It might be that you're comparing apples with oranges. I imagine they also make budget ones they don't shout about with cheaper and worse performing rubber that they sell on to companies so they can slap the yellow label on but aren't as good as higher end models.
Post edited at 20:49
