UPDATED: more pics, see below
Max (owner of Catalina) got some Hario hand grinders in and I bought one on the hopes that it would replace my Kitchen Aid ProLine for French press and Chemex brewing.
The Hario has ceramic conical burrs, a "drive shaft", a simple adjustment mechanism, and a crank... along with a glass bowl to catch the grounds and a plastic bowl for beans. One burr (large, outer) is fixed to the plastic bowl and the other (small, inner) is fixed to the shaft. The adjustment "dial" is just a nut on the shaft, really, which "screws" the shaft up and down, thereby moving the small burr closer or further away from the large burr.
I have mixed opinions on this thing, but I'll give you the punch line first: it's roughly as good as my Kitchen Aid for French press or drip grinds, and much better for espresso grinds. I'm not sure it competes with my MACAP espresso grinder, but it is impressive for fine grinds.
My mixed opinions come from the design of the shaft and the way the small burr moves. The shaft is only fixed to the "body" of the grinder in one place: the top. This means that the small burr (fixed to the end of the shaft) is free to float around away from a perfect center line. At the very fine end of the grind spectrum (espresso), this is almost non-existent because the burrs are so close together. The small burr just doesn't have any room to move laterally.
However, for coarse grinds, the burr has plenty of room to move, and it does. This means an inconsistent grind. You get some (not too many) very fine particles along with some big chunks. This is too bad, because the burrs are clearly very good, and a better shaft/body design would turn this from pretty good to fantastic (DIY project?).
However, the results are no worse (or not significantly) than my Kitchen Aid, which cost $200. The Hario costs a quarter of that.
Here is a coarse grind w/ the Hario:
And a slightly finer grind from the Kitchen Aid, for comparison:
And compared to the Kitchen Aid in size:
Bottom line, I like the Hario, but I think it could be significantly improved. It's competitive with my Kitchen Aid costing four times as much, and significantly better for finer grinds. I probably give a slight edge to the Kitchen Aid for French press grinds, but a definite edge to the Hario for espresso grinds.
And there's the "hand" part... expect to get a workout grinding enough coffee for 2 large cups of French press. :)
UPDATED WITH MORE PICS:
Handle and adjustment assembly:
Outer burr (bottom view):
Inner burr and shaft:
Bottom view up through shaft "housing":
Handle and adjuster disassembled: