Stan, I have factory old and new AA #9s, and Super Sports in #8.5, #8, #7.5. To date have not tried the #8. P-gun tubes are Briley M/IM and the repro-42's Briley IM has 0.014" constr.
The #7.5s fail at distance b/c of pattern density. #8.5s and, believe it or not, #9s are better. HS factory #9s work reliably to 30 yds plus through tight chokes. The #8.5s give better breaks beyond that. Again, have not yet tried #8s. Saving the rest of the #7.5s for rabbits under 25 yds.
Balancing percentage of "long" .410 shots vs the aggravation of loading even #8.5s on my 9000 - and wondering if they are as good as factories - decided to just buy factory HS in #8.5 from here on. I get by with factory HS and reload #9s for anything less than 25-30 yds.
Jon, You're right on all points. I shoot very little skeet now, except as practice for sporting. Also, have several lifetimes worth of Yellow Dusters and CF AA hulls (plus cases of factory AAs). Getting even a legit 1/2 oz in them makes me wonder how Winchester did it. The 205 gr drop works fine both in practice and for anything under 25 yds, so hogging out the bar is probably not worth the hassle for me.
