Nobody who quotes Heinlein can be all bad. This forum is where Deacon Matson would hang out... <img src="images/graemlins/wink.gif" alt="" />
I'm afraid, like Tom, I've never really tried the metal kind. The one you posted a link to seems to be everywhere suddenly; I don't remember seeing it at all a couple of years ago I guess I'd want to look at it to see how it's fabricated- the plastic kind has an injection-molded body (of course), I'd be afraid that seams on a metal version might be sources of slow evaporation, if not leaks- but maybe not. For backpacking, it's hard to justify the extra weight. I also chuck the key-ring immediately for use in kits.
The last few I bought were off of eBay, and they do seem to be most typically called "Permanent Match", or sometimes "Metal Match".
There are differences in quality between some and others- once I was checking out of a wine-and-cheese shop, and they had a display of these things (with various sticker-decals on them to enhance the "value") which I examined while in line. They were pretty horrible- glue everywhere, some striker rods broken and some loose.
The one I had as a kid was the one that I carried as a teenager backpacking, just a simple one sold as a novelty item, but it still lit after years in storage.
Back then I carried a Svea 123 stove, which was difficult to light with a lighter, easy with a match, and this worked well. It is certainly not windproof at all, though.
There's an old thread on them
here .
The ones I got most recently look pretty much the same as I remember, only the country of origin has obviously changed.
Haven't checked the ones in the kits for awhile; thanks for the reminder, I should do that...