Just my $0.02 but I preferred furling leaders with Danville 3/0 waxed monocord. Once furled I would soak them overnight in a film canister with liquid floatant. Eventually, I settled on using sewing monofiliment from the fabric store. A billion yard spool of that stuff cost next to nothing

Set up a furling board in the garage with two stepped-down hobby motors, batteries and a push button to control the twisting. Never found a suitable solution to connecting the butt end of the furled leaders to a fly line and finally switched to using a superglued tapered leader on all my lines. Can't beat the smooth connection for circumventing loops or knots catching in the tip of the fly rod. Moved into a new home last year and passed on the furling board to my neighbor.