..gave into curiosity and ordered a couple from the USA when these were first advertised.

They've been lost and forgotten in a box somewhere ever since..

If there was any positive enhanced tonal effect, it was too subtle
to care about.

At least the very chunky clunky Dunlop
too large for comfort and finger joint straining multi-pick 'comb' "12 string sound" plectrums
from the 90's
gave a fair increase in volume on an aggressively strummed acoustic,
before falling in less than a few minutes from limp cramped finger and thumb.