In reading everyones post, I can see that most do like the .410. I'm close to 61 yrs. old. Have been hunting since I was 14. Started off with a 12 ga J.C. Higgins pump, ventilated rib poly choke, probably weighs over 7 1/2 lbs. hunted one year only with it. Too heavy. Went to a J.C. Higgins 20 ga. ventilated rib, single non-selective trigger (Savage-Fox) weighs about a pound plus lighter, hunted quite a few years with that. Over the years collected more guns, but have never hunted upland game with a 12 ga again. Favorite gun to use now on pen raised pheasants, chucker is a 28 ga. Between the 20 ga. and the 28 ga., you're only talking 1/8 oz different in shot. I'd have to look in my journals, but I can tell you that I killed hundreds of pheasants with the 28 ga, #8, #9 shot.
The whole thing about small guages is that you have to know your limitations. Even though they were pen raised pheasants, they have a lot of fat on them, big birds, slow to get up, and make easy targets over a pointing dog, you still have to center your shots. Yes, there were cripples, but that is why you have good dogs, so that they are not lost. Wild pheasants that I've hunted years ago in Pa. are different, only because you don't get many of the easy shots. A 20 ga with a little heavier load and # 6 shot. Hunting woodcock, they only way to hunt them is with a 28ga. or .410 IMO. I do like the .410, it has it's place, and I do like them, but not for everything. Also I use 3" shells with 11/16oz of shot, not the 2 1/2" with 1/2 oz. shot.