I have to say, I believe in being armed and well trained, but I also believe that a good dog will stop most threats in your home before they get started. If the dog doesn't stop the intruder he/she will distract him long enough for you to make your first shot really count.
I have seen the alarming trend of rental units not allowing dogs larger than 15 to 20 pounds. That's not a dog, it's an upholstered rat.
I own a condo and rent it out and pay a second mortgage because the idiots of the condo association voted that you can't have a dog that is over 15 pounds. My cat weighs 15 pounds!
My dog is very small for her breed (she's a rescue pup and was severely starved when she was young and it stunted her growth) she is a 96 pound Great Dane. My last dog was a Rottie (ei, a chainsaw on a pogo-stick). I've had big dogs all of my life, mostly shepherds, and, in this day and age of home invasions and rampant teens running the streets, I won't live where I can't have a protection animal.
That all being said, kudos to the wife in this situation. I have a great deal of combat training and can't say that I could have done better giving that the two men were wrestling over the perp's gun when she fired. The husband's arm will heal. He isn't angry, he's just glad that he and his family are all alive and well.
Good for him also. No offense, but it takes a good sized pair to grab a man who is holding a gun leveled at you, regardless of the distractions the perp may have. Brave man who also deserves to be praised for his actions.