Well, I got my first set of these and all I can say is wow. My new arrows are flying like darts. I use:
2216 shafts
AL threaded insert in both ends
150 gr Bolt Sonics
2" Blazer vanes

Works great out of my Tenpoint. I need to weigh and chrono this setup. It gives me like 25% FOC, if I remember right. I can put one in each dot on my broadhead target out to 40 yards. I need to test 50 this weekend when I chrono and weigh. I think I will build 3 more so I have 6 to hunt with.