It is fabulous for heel hooks! It's grippy without being bulky, and the ridges catch well on flakes etc. It's one of the things I really love about the shoes, along with the way they construct the toe area to have semi-rigid edging bits in a horseshoe shape around soft and grippy smearing rubber across the ball of the foot.

I suspect, though, that if the shoes were a less than perfect fit it would be less useful because the shoes would slip off your heel. Luckily, the men's mad rock last is a perfect fit for my feet. I have found that their ladies shoes are not right for me, even though I am girly. As always, with climbing shoes, best to try before you buy.