bamboo certainly is not fiberglass, but aside from a good sinew backing, quality bamboo backing is superior to every other natural backing material. notice I said "quality bamboo backing". the overall quality of Moso imported from China, which is what you will get from anyplace that sells bamboo flats for bow backing, has been in decline in recent years because of the rising global demand for timber bamboo species for other uses, and for that reason, I would not trust it to do the kind of tension work I require on shorter, heavier weight hunting bows. I have not bought imported bamboo for ten years or so, but instead buying green and kiln dried Madake (and some Moso) poles grown in Florida and Georgia for several years now. it's affordable, I control the drying, and I know what I'm actually getting. I've made about two dozen bows with this bamboo, and have not had a single issue. I just acquired some more Moso and Blue Hennon from Mississippi cut by a friend of mine while he was on a trip down south. both of these are purely experimental at this point, but by all outward appearances will make superb backing material once dry. The point is, you can get quality bamboo grown in the southern U.S. without rolling the dice.