Great to see them 'for real', Vaughan. They certainly look extremely realistic, and will make a heck of a difference. I never did like PE belts.
BTW, the reason you're instructed to crumple them is to make them easier to work, and to remove the stiffness. Years ago, I managed to obtain some similar material, used to make the seat harnesses for large-scale racing car models. The more you crumple them and knead them, the softer they will become, and be able to conform and 'drape' without popping up or looking too rigid.