I've owned both XS grip2 and the XS edge. I feel the edges wear better and offer performance on solid pin point hold but don't smear and flag as well as their stickier counterpart. But I feel the construction is better and the sued upper is a little more durable.
Either way love em.
Note: if you're having problem with heel cup being to spacious down size a little more till they are hurt to the point of foot binding. Then wear the crap out of them and in a week or two they will fit like an uncomfortable tight dream shoe.