As for environmental credentials: apparently this stuff is a made from a byproduct of tofu. That should please my vegetarian friends. I couldn't get any meaningful information about the actual processing, so I can't do a side by side comparison between cotton, bamboo and soy for "green value".
The next thing to think about is dyeing. I'm going to have to experiment. I'd lumped this fibre in with the "semi-synthetic cellulose" group, but apparently it takes acid dyes well. And if it's a tofu byproduct, then mabe there's more protein in there than I thought. I don't know enough about it at this stage.
I'm still strongly focussed on getting my spinning requirments ticked off, so just now it's most valuable feature is that it is done. Now for a soy-wool blend--maybe today--and two tencel skeins. The countdown continues!