I like nitrided finishes, I have been using them on AR barrels for years and I am at the point where I prefer nitrided over chrome inside the barrel. It is tough and durable.
It is hard to design a narrow blade that is a good slicer, but I think they have done a good job on this Obake. It has a thick, maybe 1/4" spine and a hollow grind edge. First thing I check a new knife for is a wire edge. This one did not have a wire edge. Most of these knife makers appear to be using something to grind the edge that gives it a micro serrated edge that sort of gives most people the impression it is razor sharp when it is not. I got on the ceramic rods this morning with it and it kept that razor edge as I smoothed it up. That tells me they had good edge geometry when they ground out the edge. I knew it would be a good thrusting blade, but now I know it is a good slicer too.
I looked at the other models, but wasn't that impressed. I had a high school friend who got in a road rage type fight on the side of the road one night. He pinned the guy and beat him unconscious, but he took 23 stab wounds over the heart and lived. He told me he thought the guy was just hitting him with his fist, didn't realize he had been stabbed until afterwards. It was a 2 1/2" blade, the doctor told him if it had been a 1/4" longer he would had been a dead man. For some reason that has always stuck in my mind, and as a result I consider 3" the absolute minimum length for self defense in warm weather, unless all you want to do with that blade is cut yourself loose.
I am disappointed with the belt clip. The video review I saw said it came with a J clip, but mine has an over the belt clip that won't handle any belt over 1 1/2", but that is easily corrected by cutting the clip into a J. The other carry option is to use the lanyard on your belt and tuck the knife inside your pants. In this carry option, the lanyard takes off the sheath as you draw. I have been thinking about just pushing it through a belt loop and tying the lanyard off on the belt. Carrying it in the 4 o'clock horizontal position (or in my case the 8 o'clock position being a lefty) it should ride easy and draw smoothly, only problem is that is also my normal pistol carry position.
My philosophy on concealed carry of any kind is that the BG should not know you are carrying until either the knife is sticking in him, or he hears the sound of your gunfire. The life or death decision comes before you draw. That is the way I was taught and it has been the way I have taught my kids. Or as my old First Sergeant would tell me, "If it is a fair fight your tactics suck, Sir."