to me the best choice is something reliable, that you're good with, and since my 6 shot 590a1 is my primary, has the most firepower in terms of number of rounds to buy time until the bad guys decide "wow... This really isn't worth it", which I assume would occur 15 minutes before the authorities would arrive.
Like an earlier poster, I have my full size Smith M&P 9 with which I can put a full clip of 17 in a grouping no bigger than my hand at 25 yards (under timed, but not life threatening stress).