And by the way, while I do not hunt with Herters I do shoot a lot of them on clays, where they work as well there as any other shell out to at least 40 yards.

And that is typical. While shot size matters, beyond that the quality of your projectile material does not matter at all within the ranges people typically shoot pheasants at, which is 40 yards or less. You can manipulate your patterns at whatever distance you wish to optimize for with CHOKE far better. Thinking you can fix a problem hitting pheasants solidly by changing shells is a prescription for accumulating frustration that I have seen play out many times.