I have had both GWP (two) and an Anatolian. The Anatolian was full blooded her father came over from Hungary. He was a massive 200 lbs routinely killing and burying anything that didn't belong in the goat pasture. Everything from coyotes to lizards to the neighbor's black lab, if it crossed onto his territory it was toast. His daughter grew up to be just like him. If a GREAT guard dog is what you are looking for, then an Anatolian is a great choice. I thought our Anatolian was much better at protecting then either of our GWP were. Our Anatolian had a much stronger protective instinct, and didn't roam which both of the GWP did! She actually chased a bucking mare for a quarter mile before letting the mare go.
My only word of advice to you is make sure you look carefully over the puppies (if you start out with a pup) and go with the most social, friendly one. Our problem was that DH choose the largest female out of the litter instead of going for more family friendly personality traits. She was MUCH bigger then her siblings but she wanted nothing to do with my husband or myself even at 6 weeks. Every time she was pulled from the puppy shelter and placed in front of us, she would go right back to the shelter. When placed on her back while holding her, she would fight fiercely until put down. but DH wanted big so big we got. She was a protective dog, friendly, but she did nip at my hands. When I wasn't looking she would grab my arm in her teeth and hold me as if to say "I'm boss here" and would come from behind and knock me to the ground. I would say that she needed a lot of training but at over 70 lbs at 6 months and nearly half my hight (I'm 5'8") she was just too big for me and much too big for our nine month old son. We finally gave her to a friend where she is a very happy flock guardian, and loved to death by a 16 year old. Please understand that she really is a great dog but she had a personality that belongs more with a herd of goats then with a family. But if you go with a dog that has the right personality (more social) you will have a great mix of livestock guardian AND family friend. Best wishes to you in your search for a perfect friend and guard.