This Website consists of FG bows and wood bows, what the hey is wrong with using a synthetic backing. Backings I have used Nylon, Polyester, FG, brown bag, silk, Linen, Oak and maple. As far as brown bag, linen and silk go I found no strength at all using those. Polyester is hands down the best I have used..! Its thin fabric so it does not add any weight. Anyway its simply a Hybrid bow.
I don't use Sinew because of the application process.
The problem I had using FG is not over powering the belly so much as it increased the tension so much that the bows snapped.