1. The high BC of the new 53gr Vmax will show the same benefit in both regular 223 ammo and super performance ammo in terms of superior windage, less drop, and retained velocity.
2. Advertised velocity claims are generally exadurated and very few actual shooters will actually get those velocities.
3. Test barrel was 24" on an AR, which is not a very common barrel length. For a strictly varmint rifle, maybe. But most AR owners use far shorter barrels, which will decrease the velocity.
Summary: Hornady has produced a new 223 53gr Vmax bullet that is much more "aerodynamic" than other bullets in it's class. Cool! It's being loaded in a new breed of factory loaded ammo and marketed as nearly equal to a 22-250, which it's not really.