I have bought a couple, keeping one, giving one to my son. I think the ones I have are the genuine article, made by Mr. Nagao. It has been several months, so I forget what the indicia of a genuine Higonokami are, but the information is readily available on the 'net.
The laminated blade came extremely sharp. I have not tried to sharpen it.
The big river site has both the genuine ones and some off brands. I have read some criticism of the blade geometry, but I don't really know enough about the subject to judge it. It does the typical EDC tasks quite well. I haven't tried it as a vegetable slicer, however. The wedge-shaped cross section may keep it from slicing as well as, say, an Opinel.
It is quite slim, and shorter than my other folded-metal knives, so it is quite unobtrusive in the pocket.
I like it.