There's been a fair amount of discussion on them over on
coffee-geek[edit: Nope, over on home-barista.com, please see linkie below], I think. As near as I can tell, they're a very good hand grinder, but I've never owned one. They're probably less well-known and less popular than, say, Zassenhaus or PeDe/DeVe grinders, and OrphanEspresso says they've never worked on one that would do a decent espresso grind.
[n'other edit: I read that somewhere, but it doesn't look like it's in this particular thread ... and some of the people say they're happy with these as espresso grinders. I'm pretty sure that varies grinder to grinder, not brand to brand.]Linkie:
http://www.home-barista.com/grinders/hand-grinder-jive-photo-essay-t4482.htmlIf
espresso were all I were looking for, I'd pass, but if I wanted one for drip or to give to someone, the four you snapped there look like they'd clean up nicely. (I like hand grinders, though. Someone who just wants easy coffee of a morning might not want one at all. They add a couple of minutes to the process which I enjoy and which someone else might not.)
They also seem to sell moderately well on eBay, if you're interested in that at all.
Hope some of that may be helpful. (On the one hand dis ... on the other hand dat ... I probably need more coffee, myself. The plural of "dat" is "data" -- yes?
)