Oh my! I like the 58mm!
Good write-up! ]I have the four-layer version, and like you, initially thought one of the thinner versions might be a good keychain knife. YMMV, but as I considered it further, I realized the following:The #1 reason I carry a key chain knife/tool is for the scissors, and the Vulpis scissors aren’t on par with Vic scissors.If the saw and scissors on the Vulpis aren’t worth having, then we’re down to the two-layer version. But how does that compare to, say, a Vic Cadet? The Cadet provides more tools at a lower price point.In fact, I would say the only clear advantage for the Vulpis over the Cadet is the blade steel. But then again, I don’t do much cutting with my key chain knife blade; I’m pretty much always carrying a larger knife as my main cutter.
I've used the scissors a few times, and thus far they've proven more than adequete. The Vic scissors are world class, of course, but the Vulpis has opened a bag, trimmed a bunch of threads, and all those sorts of things perfectly well. I'd rate them above most of the Leatherman scissors, and on par with (or maybe slightly better than) the "good" Gerber ones (the old rounder ones they used to put on the MP400).In my mind, there's a line between the 58, 65, and 74mm lines and the 84s. The Vulpis is more matched up against the former (like you said, a keychain knife). In which case (for tool options) you're deciding between a nailfile and scale tools vs a can opener (pending forming an opinion on the iffy saw). For the other tools, I think Fox is marginally ahead. They get an advantage on the blade, bottle opener, and drivers in most cases, but Vic the scissors and drivers if you need tiny ones for electronics and the like. I guess it comes down to use case, but I'll take the bigger drivers and blade in exchange for good-but-not-great scissors. If the old 74 line still existed, it'd be much stiffer competetion (I'm happy carrying it for the month, but I don't see it bumping the Executive off my keychain), but against the Classic SD/Rambler/Manager I think it's an upgrade in most cases.I've tried it a few times, but the Cadet has awlways been too big for me on a keychain. As a dedicated pocket carry, it's a little more complicated. Since you can't get scissors under 91mm anymore, that's a much bigger jump for people who want scissors w/ the traditional blade and opener set (and/or want something bigger than the 58, but not jumping all the way). That's the wife/office worker catagory from yesterday. I need to check, but I think the Vulpis is also (per layer) thinner than the 84s (closer to the 58s), which factors into the bulk as well.