I'm working on Gunnar Brammer's Chosen One streamer pattern. These hooks (Gamakatsu B10s #1/0) aren't quite big enough for the full fuzzy fiber head. If I drop down to a #1 or a #2, I can tie the same fly and leave the head off; I think they will make really nice deceivers without the bulky head.
This material is a kanekalon product called Easy Braid. It is way less expensive than the premium craft fur products marketed for tying streamers.