I have one which I carry off and on. It was my first foray into "real" knives after a childhood of swiss army knives and a small collection of leatherman tools. It is solidly built, fairly customizable with 4 different clip options, and feels good in my hand.
After 2 years I have found the undersized torx mounting screws to be insufficient for the task of holding a knife to the pocket and contending with bumps and snags. 2 of the screws have stripped and fallen out, and I have had to move the clip to a different set of holes after my preferred site totally stripped out.
The blade is ok, it will take an edge but daily use wears it down far more quickly than a Benchmade or Emerson.
The back lock is solid. I just looked at mine this morning to take the dremel to a detent that lies at the half way open point. I have yet to figure out what purpose this serves other than perhaps slowing the closing action in the interest of finger preservation.
I found it for about $35 shipped on ebay back when 5.11 first started expanding from pants and shirts. It has served me well, but for the same price range a whole lot more knife can be had.