i just finished a quilt using the newer bamboo and cotton bat.
i prewashed it and all the other materials too, but i would hazard a guess that it shrank a full 5%. the quilt is pretty crinkly now, which i really don't mind but was somewhat unexpected given that everything had been prewashed and machine dried.
it was nice to work with, but linty once i got it into the machine to quilt it. i chose a bad quilt to experiment with, as the top has quilt a lot of black and the backing flannel is entirely black.
i am sleeping under a quilt that also uses it and it seems pretty warm, though nothing matches that hobbes wool. i haven't washed the log cabin yet and now i'm a little more nervous about that than i was, but it will be fine. i'll hang dry it and hope for the best.
so that's my review. it wasn't a disaster, the price was okay, but i think i'll stick with either 100% cotton or wool from now on. that prewashing is a pain and i would rather not have to bother.