Backer rod looks very nice, problem is just, it's too rigid. I use 15mm backer rod, so it's not THAT thick, however, it barely moves - or "swooshes".. Also, I couldn't get any plain black one, so I had to paint them grey ones black. I used acrylic paint, which is obviously pretty flexible, but not so much as to not have to be careful with your movements. Either way, the whole bunch of dreads (~50) is way too stiff if you put the bio and underhelmet on. Don't know how you do it, but I think it is very nice for display and otherwise sucks.
the bike tube dreads however swoosh really nicely and look quite cool. I haven't done a full setup yet, so that remains to be seen. Looks promising though.