I bought a pair of Merrell Moab Ventilator's for my thru, the shorter cut ones not the mids, and they feel great and are comfortable. Also picked up a pair of blue superfeet from my outfitter for them as he suggested these would be the best insole choice for me. Only problem now is one of the boots has no play in the heel at all and the other my heel somewhat slides up and down a bit and I am concerned this will cause a problem after hiking long days. Is there a fix for this I have tried one different lacing technique to try and lock my heel in. These have got to be the most comfortable pair of shoes I have ever owned for hiking and I would hate to have to return them and look for another pair. I just dont get why I get heel slip in one and not the other.