Sam, your telling me that at 2-7 feet a 20 ga. shotgun firing a mass of small bb's out of a full choke would be less than effective?
The question has gotten a LOT of mileage here on THR. I'm not going to give you every lick and blow of the debate. If you are curious, please search our archives for more information. Suffice to say, it is generally considered that birdshot (which generally weigh less than
two grains) do not sufficiently penetrate any medium far enough to reliably cause incapacitation.
You may argue that they would be very distracting (especially if you feel that you can always hit your opponent's bare face), and might be alarming enough to cause them to flee. But, a shot over a few feet away, at the center-of-mass of an intruder, especially one wearing more than a minimal layer of clothing, will not penetrate far enough to do the kind of damage that would ensure they cease the attack.
The "Box-'O-Truth" website gives some pretty illustrative examples of this using various test media. I'd encourage you to thoroughly read their report(s). Or, as I said, do a search here on THR for similar information.
I have done so, as well as participating in a number of threads here and making penetration tests on my own. I choose to keep my HD shotgun loaded with buckshot and with slugs on standby.
You'll have to make your own choices, of course. Sounds like you already have.
Wow. O.k.
-Sam