As an aside, I really like recurve blades. But...one of my favorite folding knives is the Kershaw Shallot. The ZDP-189 version of this knife has steel hard enough that it can only be sharpened by me using my diamond stones and I could not get the 1" wide stones to fit within the recurve portion of the blade. I was stuck using Smith's diamond rod until, out of frustration, I reprofiled out the re-curve. To do a decent job on this knife steel in its recurve blade shape I would ideally have used a spyderco sharpmaker with diamond rods.