just remember that the bands will now be pulling more downward than the original euro muzzle. i tried it on my omer, but didn't like it. when i went back to the orig closed muzzle, i just used dynema as my wishbone instead of the metal. i also had to file(smooth) out the notches so it wouldn't cut my softer wishbones. (with one band, that gun has no shaft friction leaving the barrel whatsoever)
i've talked to sterling at hanapa'a quite a bit about this, and although it's quite popular over there, he still prefers the euro muzzle.
the only gun i'd see the open muzzle working on is a rob allen railgun because of the full length track.
if you know how to make delrin spot tracks, then that would be your best bet. i think two spaced evenly between the handle and the muzzle would suffice.
good luck,
anderson