I've had two, the first a female that came from champion eastern European working stock (very expensive), the second a reputable, but not really expensive breeder. The first died young of a rare disease, but she was a spectacular dog, willful, but trainable, and as clear headed as I can ever imagine a dog being with threat assessment. She could seemingly read human body language with amazing accuracy. I was always vigilant, but she could be trusted with other pets, small children and adult visitors, you name it. Before I got her, I spent countless hours preparing, and even once I got her had a trainer work with us. I think unless you are experienced in large canine behavior, this is a must.

My second GSD (a male) didn't have the blood lines, but he is very smart, but a bit more wary of people. I watch him like a hawk, still use treats when visitors come to the door to associate invited visitors with something pleasurable for him, and he generally does fine, but I'm always on alert when we have visitors and he's out of his kennel. I just don't know that he has as much of a "threat discernment" knack as my first dog did. He had been very easy going and tolerating of my young nieces and their little Boston Terrier as well as with my oldest daughter's Heinz 57 dog. Even being an experienced owner, I had a trainer work with us with him as well. He is an exceptionally good family pet, and because of his protective instinct, a serious threat deterrent.

As a breed, I love them (have to vacuum all the time), and I love observing how smart and anticipatory they are. I walk mine about 2 miles every morning, and we all spend time with him, so he isn't bored. I didn't have an issue with my homeowner's or umbrella premiums (State Farm), though I had always heard that. I will say with no uncertainty, that a prepared and committed owner is an absolute must to being a responsible GSD owner.