I like using natural wool. It seems to quiet very well, and allthough I haven't compared my speed through a chrony, I can't tell it robs my speed any.
Lately I've began using the synthetic fleece silencers again. They also do a great job silencing, but they don't look as cool as wool does.
But the catwhiskers, limb saver silencers, and other new fangled silencers seem to do just as good. I think it mostly boils down to personal preferance, for the look you want, whether modern or traditional/primitive looking. When I messed with wheel bows a bit, and was caught up in the speed thing, they're was only 1-2 fps between several different silencers.
hnh