This is almost the equivalent of a Barefoot Chameleon 4 Stretch. It is my first of Blaze series. Being a minimalist shoe it does not have a removable insole, however, it certainly does not need one, given that it has sufficient cushioning and arch support built into the shoe already. It certainly redeems the idea of the Proterra Sport having only a 6mm drop without the bricklike sole. A vibram sole is a definite plus. I would point out (since the sole patterns are no longer displayed on the merrell website) that the tread pattern is far more creative and useful than the boring, incomprehensible pattern found on the Proterra. The overall comfort of this shoe has no rival of any in its class.