I have one (got it from Brigade Quartermasters I believe) and it is a nice knife. But it has it's bad points along with the good.
It is a slick little knife, carries well inside my pants, has a good handle, and opens very well.
But the liner lock does not (in my humble opinion) engage enough metal on the blade, and I have concerns about how effective the blade is.
My current carry knife is a CRKT M16-12Z. It has a heavy and sharp 3" Tanto blade, w/serrations, the "Carson Flipper" which aids the opening process, and a good liner lock. Plus it is about $20-30 less expensive...NOT CHEAPER...just costs less. It is not quite as slick as the A-F, but I think it's a better carry knife. I recommend that you look at CRKT before you buy anything else.