Robert, all I can say is that on heavy bone impacts the GrizzlyStiks are the most durable of all the carbon shafts I've tested so far. Must add that I have never personally used the Sitka version, but Cher has. All I've used were the Alaskan, Safari and Big Five.
I like that Ed Schlief CONCENTRATES on trying to develop arrow components designed from the ground up for HUNTING ARROWS. He doesn't make 'target arrows' and then try to dress them up to promote them as hunting arrows.
Do I think there's room for improvement in the GrizzlyStik shaft? I think so, and Ed keeps tweeking the design, trying to improve them. Are they the arrow shaft for every shooter? Decidedly not.
Their biggest negative, to me, is that the tapered design has to be bare shafted by cutting them down from the front, rather than the rear. That means the insert has to be removed and reinstalled every time I shorten the shaft. The AD's share that problem. Is it a BIG problem. I don't think so.
BTW, Cher has lots of arrows too - but not nearly enough!
Ed
TGMM Family of the Bow