Is anyone still using Kapok? Particularly in bottleneck cases?

All you ever hear about in manuals etc. is Dacron, but personally I've never been keen on the idea of sending burning plastic up the barrel.

An old guy at my club (who did some very high level competitive shooting in his day) swears by Kapok as a filler.

I bought a bag off but haven't tried it yet. I wanted to get a few opinions seeing as the internet doesn't bring up a great deal on it.

Cheers
Greg