Lanvin, Balenciaga, CP, a bunch of people use Margom (sp?) soles. Definitely super legit in my opinion. It seems I can wear a pair of Achilles forever and then still sell with tread left.
Since you're curious, here's a reference pic of my current pair. These have about 50-60km on them according to my iPhone. The only wear is what you see at the heel from me lazily dragging, the rest of the sole is practically as new.