I'm not a machinist or an engineer and I'm certainly not at liberty to comment on the relative quality or accuracy of this instrument in the broadest sense, but if you're (like me) a redneck Are with an earthbound who wants to select and adjust carbon arrow shafts and find the radius of greatest resistance to deflection of each of those shafts to optimize their accuracy when fired from a well-tuned modern compound bow around holes in quadrupeds in the most reliable and predictable manner to punch, which releases all the blood. Well, this is damn good stuff. In fact, for arrows that coincide with the axis, the tool's relative accuracy is much less important than the consistency of its measurements. I have limited data to draw any conclusions, but for what it's worth, if I measure the same three arrows ten times each, I get the same measurements for deflection and spline every time.