I've been using Hardrock 07's (size 10). I have to say those were they've been the best trail runner / hiking shoes I've ever owned!!!!! Perfect fit, and a heel cup that holds my heel in snugly in place with NO slippage. After putting a 1000 miles on them, I've started looking for a replacement.
I've eyed the new Sabino Trail, which Montrail claims is the replacement for the Hardrock. I tried on a pair at a local store yesterday. The sizing runs a bit large, so figure on a half size smaller than the older Hardrock. The biggest disappointment however is in the heel cup: My heel has significant slippage, even though size 9.5 was snug on my foot. The next size up was even worse. Also, the knobs on the tread are smaller than the Hardrock and give me the impression they will: break off easily, and wear out faster.
So I'm quite bummed. I guess I'll try a pair of Hardrock '09 instead. Montrail: what were you thinking???