I’ve used otter or beaver fur strips for years, but recently put some mini-woolies on my new Kanati. One thing I really like about these is that after you place them in between the string strands and tie them down, they are very secure and won’t move around while shooting, but you can still slide them up and down a bit for fine tuning. Not as easy to do with fur strips, which need to be removed completely and then re-installed.
As a side note, I much prefer the size of “mini” Wooly Whispers, but the only place I can find them is through Kustom King. Not sure why. I like them a lot more than the standard Woolies, which are usually way too big for my needs.