because most guys who breaks into houses are crazed drugged up moros. I dont think the size of the gun matters but more the what you feel comfortable with.
for example I took my gf to buy a 9mm handgun but the sales person keep pushing the 357 as it had more stopping power. when I explained that she didnt feel comfortable with the 357, he still kept pushing it. finally we walked out without buying anything.
I think you should just get what you feel comfortable with. what's the point of having the biggest gun if after the first shot you are gonna be shooting up into the ceiling. or perhaps you hesitate because you know you cant handle the recoil.
semp