The Klein power nut drivers in 5" are almost exactly what I’m looking for - but they’re only available in 7/16, 1/2 and 9/16 sizes (was hoping for full sets.) Looks like they have some shorter hollow shaft variants for 1/4, 5/16, and 3/8 that would probably still work for me, though. I’m not an electrician, so that’s probably why I haven’t seen them before; never even thought to check with Klein, since I don’t really think of their brand for this kind of tool. I suppose I could continue getting by with the non hollow shaft drivers for the occasional metric stuff I run into. Was just hoping to get a whole matching set to satisfy my fetish for tool uniformity.