Coat hanger and #9 wire are stiff and sorta hard to work with. But they will do the job.
Are you folks using a whammy? Just make sure your whammy (rubber tube or cone shaped spring) is large enough for wire to fit.
Twisted #11 wire welded to a 40D Spike with welded washer to keep it form spinning.
Nice and stiff yet still allows it to collapse so it doesn't become an entanglement. Works fantastic. I've got about 200 made up.