James Yeager of Tactical Response makes the case for the Mossberg 500 with a youth stock as a primary home defense firearm. He couldn’t remember the specific model number while filming the video, but it appears to be the 54300.
20-gauge shotguns have far more power than any pistol, and are also easier to aim and fire under stress. Yeager doesn’t mention load selection. For an “in-home” gun it is my opinion that #4 buckshot is the best compromise, as larger buckshot and slug loads post a much greater over-penetration risk, while birdshot loads (including waterfowl loads) do not consistently penetrate deep enough to ensure stops.