I prefer light buck loads. Overpenetration, in my opinion, is a myth and a complaint for a problem that never existed. Penetration is the most important feature in ammunition that you expect to stop in one shot. Nothing is more devistating than a shotgun at close range. I have a pistol handy, but, the shotty is not far away. If I have to use my pistol, oh well. If I can get to my shotgun, God help the sorry bastard that broke into here.
I want to use the most effective tool for the job. That tool is a shotgun in my opinion. A shotty is about a 30 yard weapon as far as I'm concerned. Carbine is a 50-150 yard weapon and after that it's battle rifle, followed by bolt gun. That's not to say that an AR wouldn't work, it has a lot of advantages, especially with the size of the magazine on multiple attackers. Either way, I want the most effective tool, and IMO, that is a shotgun loaded with a 2 3/4" buck load.