My 870 in 20 guage with Remington Xfull choke loves those Fed HW 6's! Not so much with the #7's. I am sure the right choke tube would change my tune, but haven't found it yet.
I am sure this is Spot ON.
I have seen posts on other websites which detail that FED HW #7s will shoot lights out with "X" choke tube, but not so much with "Y" choke tube.