I have:
Stiff KISS
Neck PECK
"Classic" KISS (clip point)
I also handled all the other models at the Japanese knife show. I'll be getting the Bear Claw and some others later.
I wear one of the neck knives at all times. All are sharp as the proverbial razor. I have very fine hair on my arm and back of my hand. No problem. Taking edges and corners off paper. No problem. Only the tanto tip of the Stiff KISS is a hassle to sharpen. The Neck PECK is a double, double bevel flat grind.
The tanto blade of the original KISS also "feels" thicker and not as sharp as my "Classic" KISS. The thinner edge with hollow grind allows me more control than with the tanto tip of my Stiff KISS, and seems to keep an edge longer, but it's still a single grind. Perhaps one of their other all-metal models, like the M-16 or Mirage Grey Ghost would be more to your liking.
Since the forum complaints this week, I can see how the KISS lock will not hold up under any counter-clockwise blade twisting, but I still love them, and will get more. Since I bought it direct from the distributor, I was able to hand select the knife with the best lock.
Eric Takabayashi
Fukuyama, Japan