have thought about this more than once, and tend to feel that a .357 mag in one hand with a flashlight in the other is my best option. I don't want the light to reveal my exact location. With a revolver in one hand, the light can be held in the opposite hand away from my body and my weapon.
If I truly felt the intruders may be wearing body armor, then I agree with the AR or a 5.56 AK, this is the better choice. I like my shotguns, and they deliver tremendous power, but I have more confidence in the penetrating ability of the 5.56 x 45. If we are talking level IV vest, then it would take multiple hits to shatter the protection, and a high cap mag would be just the ticket.