RE: horns
Ditto. Those are nice stiff structural members and nicely made, but as Ed said those materials have lousy properties as a bearing surface. If you were to use a nylon clevis in them, the CF laminates would abrade the pins to nothing under vibration and flight loads. I like those Sullivan steel horns with the nylon insert.
Good to ask - that is a critical area in which to experiment with alternate materials.
MJD