Yeah, that's right, a lot of people disagree with you so they must all be wrong.
Personally, since the biggest threat my "flock" faces is the neighbor's dog, and I'm in an area where I can shoot dogs that bother my flock, I don't need or have a LGD at all... but if I did, you can bet I...
Pits aren't intimidating to coyotes and coyotes are known to attack them. http://newportbeach.patch.com/articles/pitbull-attacked-by-coyote Beyond that, they are bred to fixate on a single prey animal, which means a couple pack members distract the pit while the others eat the cats, chickens...
"...but mine will even herd cattle."
Isn't that a sign that they aren't really suitable for the LGD role?
I don't have experience with LGDs per se, but I have experience with a 2.5 acre fenced yard in coyote country, and various size dogs. We had dogs that were about 40lbs, about 60lbs...