Who has tried synthic?

I've tried the fat polyester yarn from Jo-ann fabrics a little bit, which looks like Synthic. But I guess it is different from the real thing.

 

My limited experience with both Synthic and "Scrubby Yarn" shows that both are very good for growing algae, which, along with the water that both the fibers and algae carry, makes it compress into a root-suffocating mass more easily than even real sphagnum.

 

my experience with it is that it shares one main drawback with sphagnum: when bone-dry, its extremely hard to re-wet. Of course when the material is just out of the bag, its very hydrophilic, but this changes quite rapidly after a few weeks-months in the greenhouse, when its surface has been made hydrophobic by biofilm or the like. As Ray mentions, if maintained in a continuously wet state, it may lead to the same problems as sphagnum, mainly roots rot, but then it depends on the type of orchids grown. Lepanthes or cuthbertsonii like it, as long as the surface doesn't get covered by algae/mosses.
So, for me, this material is no miracle, but compared to sphagnum, it has the advantage of never rotting. I now like to use it sandwiched between hard wood mount & Sequoia bark slice. In this situation, it doesn't get algae clogged, and so is the ideal "rewetting buffer" in between waterings. I'm also trying it with excellent results as substrate for Dracula's in hanging baskets. Its a low-light situation, and the algae are not a problem. I've tried it as only mounting material for Dendrobium vexillarius, and after 1-2years of fantastic growth, the "too wet because of algae growth" situation killed many plants. I don't think sphagnum would have done better, anyhow. Or live sphagnum, maybe, but that's another growing technique!