I really have a hard time wrapping my head around the new idea that the .410 is a great defensive round. No doubt it will work, but so will a pointy stick. The #1 rule of any defensive gun should be "practice". If you can afford to run a couple hundred of those exotic .410 rounds thru your weapon every couple of months then more power to you. And the arguement "a hit with a 22 beats a miss with a .45" is pretty well countered by "a hit with a 45 beats a hit with a .22".
John A. Monroe, Never Forgive, Never Forget, Blood Pays Blood