The BF1 is TINY compared to the others. 2.75" blade, 3.75" handle, approximately. Liner lock. But it is strong. Compare it to most other knives its size and you would be willing to beat on it where they would fail. The pivot is a regular slotted screw, easy to tighten up.
Next to a PT or Sebenza, it's probably close to their class. I have the even smaller Umfaan, and that's probably stronger than the BF, but it's hard to say, since I'm not abusing that class of knife.
I should say, I got it for when I'm only going to carry a small knife but I want one I can rely on. I got my money's worth.