Yeah, it's a matter of personal choice, I suppose. I could use my 1911, but I've decided on the Remington instead. I'm considering a Mossberg with an 18" barrel, though. They're cheap enough and very reliable shooters. Still, given the layout of my home, it doesn't really matter. It's small, and the setup works just fine with the shotgun I have on hand.
Another factor is my wife. She's not at all comfortable with the 1911, although she can shoot it fairly accurately. The shotgun, on the other hand, doesn't bother her, and she's quite good at stationary targets with it. She does complain about the recoil, but she won't have to fire it too many times, and in that situation, she won't even notice it.
I've run through some tactical drills with her in the house, so she won't be facing an unknown situation.