Yes, the heel is baggy, but that is why you buy them in your street shoe size. Five-Ten makes their shoes small, so your street shoe size will be tight, which means don't go any smaller like I did, or you'll be knuckled up like crazy! As anyone will tell you: Stealth rubber is the stickiest! The old C4 was stickier than anything on the market, and now Five-Ten makes the Onyx and HF rubbers - are you kidding me?!
I have a pair of Pontas that I couldn't get to stick on some non-existant feet of a sit-down-start. I threw the ol' Anasazies on and stood up like my feet were flat on the ground! Huge difference in performance!