Glad you liked it. Technically I could have beware of Mossberg, S&W, Ruger, Para ordinance, Colt, Remington, and about five others added to such a sign as I am a collector. My Mossberg 590 and my Para Ordnance .45 ACP are my dedicated HD guns though. In ref to your question I have been told by a friend who is ex Army turned police officer, that if you follow all steps to a normal escalation of force before you shoot then legally you should be fine. There are exceptions to this such as using exotic ammunition etc. If you shoot a person using a terminator round or a load of flechette then it may be hard to explain that one.

If you find someone in your home and give them a reasonable warning and they still intend on doing you harm then you should fair off well in court if you shoot. If they try to run and you chase them down and then shoot them in the back then your court case may head south on you fairly quick.
If there is only you and him then I guess there may be only one person left to tell the tale anyway. Much better to be judged by 12 than carried by 6 as the old saying goes. I think if you shoot him in the groin with a load of #4 buckshot , smash him into a bloody jelly with a bat or cut him limb from quivering limb with a hooked machete then your case will be no different in front of a judge as there are no different levels of killing, dead is dead. If you torture him before calling the cops it may be looked at differently by a Judge I would imagine. I think being Military that my service to my country would be taken into account if I were the one doing the answering in court. (At least I hope so) Hopefully anyone who attempts to gain entry into my house whether I am home or not gets the fear of God put in him by my dog and decides to abort mission before it ever comes to the need to shoot him.