I'm always trying different arrow shaft materials, just 'cause I like to. Laminated birch shafts are very nice. Straight, heavy, and tough. Heat straightening over a stove works well for new shafts. They seem to stay straight, too, unlike many hardwood shafts. Though they're not as tough as maple or hickory, they are tougher than douglass fir or larch and worlds tougher than cedar. They are tough enough to have split a field point on one tough hit, but for the shaft to have remained fine. Mine are 55-60# spine, 21/64" diameter (oddball diameter used with these shafts), weigh 500-520 grains raw shaft weight, and finished out at 650 grains when cut to 27" (BOP) and tipped with 125 grain points.