Hi Lamaster,
A Pyre would be a great dog if your are looking for a livestock guardian rather than a dog to help you work/move livestock.
They are gentle and calm, but will fiercely protect anything that they consider part of their "pack"...be they cattle, goats, chicken, children, etc. They will roam far and wide patrolling their territory, and tend to bark at night at anything and everything they decide is out of the ordinary. And they are big!! Most, both male and female, are over 100 lbs. and about +/- 30" at the shoulder, with males usually being at the upper end of both ranges. With their thick, long double coat, they handle cold weather without a problem, but will suffer in heat, make sure they have lots o' shade and water available! From what I've seen, hip dysplasia seems to be the health problem to look out for.
They tend to be a bit stubborn and strongwilled, but like any dog, they need to know who's boss, and benefit from consistent but fair training, and lots of love. The are a bit aloof to strangers, but very loyal to family.
Good luck puppy hunting!
April Z.