I thought they might help and bought a Wilson 45acp and a 223 CG. Turned out that when I taper crimed enough to get em to go in the 45 CG, that I lost my headspace and the rounds would chamber too far giving me failures to fire, hard ejection, and rifiling marks on the brass. tossed it and everything is fine again.
My 223 CG never helped me find any out of spec rounds, they always go in it and even if it shows brass too long it dont show length. I always trim anyway for conformity.
Verdict? Cant see a real need for em'. I'm sticking with calipers.
YMMV.
