@farmerman,
u brought up fila braseileros.
they are widely renowned as the best guard dog money can buy.
the aggression towards "strangers" is a very distinct unique and desirable part of the breed.
(hrmm, south america? wonder why they want such a vicious and powerful guard dog, with scenting capabilities of a bloodhound...)
CAFIB sets the standard for them. there is also another organization but i forget what it is, cafib is more popular though.
now the pitbull on the other hand, any human aggression period is undesirable, obviously.these are the only dogs i know of that are bred specifically to not attacks humans.
they arent even good guard dogs. i walk into my friends abckyard he has 5 dogs 4 are pitbulls.they never met me before. im just like HEY whatsup pretty pitbulls!
they were wary at first, but i just acted confident and they were like YAY! playtime!