The AFCK is a better all around carry knife. The plain edge blade is good but the partially serrated models have the best of both worlds. If you really need to get the BT blade, you may want to go ahead and buy the M2 (toolsteel) AFCK. I don't have one in M2 but what I understand is that they are tougher and hold an edge even better than the ATS 34 models. The Axis Lock may also suit your needs, it is very similar (size wise) to the AFCK, and has what some consider a better lock mechanism.
Another thing to consider about the BT (black) blade is where you live and what your uses will be. The black blades look nice until you really start using the knife and the BT starts wearing off. If you are in a humid climate and not able to take care of your knives with reasonable frequency, the BT would be a good investment.
Others to consider:
Emerson Raven (clip or tanto)
Emerson Commander (my favorite)
Outdoor Edge Impulse (budget knife)