Ive used it, though I did my own heating, not easy, but at the time it was not available re-primed. I thought it was okay, not bad, but not worth the price and hassle. Ekowool is similar in characteristics. I think that the one Xc...... it rather expensive at 8.00 a ft compared to aprx 1.60 a foot of Ekowool. I also noticed that the XC had more of a "taste" compared to Ekowool.
SOme people love the XC cord, but me , I need to watch every penny.
I also found it a bit dusty and had a sore throat. The people I knew who used it were really into TH, so maybe they didnt notice it.