Tim, I agree with you on just about every point, but there is still one big reason I don't have one. It is a bench top only vice. I can't set it up at a height where I can use it. At least not without building a new bench specially for it. I have tried a friends and it does what it says on the can. The lack of height adjustment rules it out for me. Which is a shame as I can see it making a significant difference to tying speed.
Please think about how much thread you waste leaving a tag long enough to snap off each time you start the thread. Some of those bits you discard are long enough to tie a fly. I go through about 8 to 10 spools of UTC70 in black a year, Tying mostly in the 14 to 18 size range. That costs me about £18 ($27), doubling that cost is a significant hole in my profit margin.
I noticed you break the tip of your peacock herl after tying it in. A way to avoid this, once you have admitted the tips will break, is, rather than trim the tips off, (guesswork) hold the herls over your thumb nail under moderate pressure, and, holding the buts firmly, run your thumb nail down them. The tips will all snap off at the first weak point, leaving you a nice even bunch that doesn't snap off when tied in. I hope it helps, by now it has saved me hours of wasted effort.
"Political correctness is a doctrine, fostered by a delusional, illogical
minority, and rabidly promoted by an unscrupulous mainstream media, which
holds forth the proposition that it is entirely possible to pick up a turd
by the clean end"