I have been using high-brass Federal #4 3-inchers since 1996, and I have to say I really did not notice a big change when they switched to the FC wad. At the time of the switch, I was shooting a ported barrel and a ported choke.
Sometime after the FC wad came out, I read about the problem and I switched out the choke with a non-ported Carlson's Dead Coyote and got a slightly improved pattern.
