I use 9 shot on a regular basis for Gambels quail, I also use 9 shot much of the time for wild chukars, as do my hunting companions. I lose VERY few birds that are obviously hit from crippling over the course of the season. Most birds are killed outright. I hunted S. Dakota for many years shooting 8's at pheasants. I have shot 8 1/2 as well. Never seen 10's and I think they would be smaller than I would choose for anything but quail.
Most shots are over points but many are not.
I grew up in Vermont shooting some pretty wild Ruffed Grouse. We always used 8's. We had no access to 9's in those days. I just returned from Ontario on a Whitetail hunt and I spent a morning shooting Ruffs. I shot 4 birds flushing and killed all 4 dead using 9 shot in a 28 gauge gun.
If I thought at any time that smaller shot made me less effective I would change immediately.
