They look fine and I'm sure will catch plenty of fish. Started using mallard feathers over 25 years ago with great results and it's hard to try something else when duck feathers work so well.
I have a bunch of them as well and like them a lot, just curious about the Guinea feathers. Have always liked your duck jigs too!
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Peak Vise Dealer
Tying Materials, Chenille and Hackle For Pictures of my Crystal, Nylon/Rayon or
New Age Chenille Please PM Me! Also I
have the Saltwater Neck Hackle and some
colors of Marabou plus other things!