The fundamental, real, difference is 1/8oz of shot. 27 pellets of #6. The sparse pattern can be filled up by going to tighter choke, if you can control a slim light gun well enough to center your birds.
You know, I've heard at one time or another that a 410 will do everything a 28 will, a 28 will perform as well as a 20, nobody needs a 16 anymore because of the 20, a 16 is indetectable from a 12 as far as performance, and there's no need for a 10 because of the 3" 12, and better performance ammo in the 10 obsoleted the 8.
By logical construction, a 410 then is adequate for any task including 60 yards honkers.
Sillyness. As an old (and geting older) trap shooter, I can't control a light gun worth a damn. I like to carry a light gun, sure... but when the time comes to actually kill something, a little heft helps. I've settled on a 687L 3" 20. The gun has a 28" barrel set and moves well. Good compromise. It's the lightest I'll use in the field.
