It all comes down to how they are raised. I showed some property couple months back. Pitbulls were in their kennels and only woofed to let you know of their presence. They sat in their kennels and just happily wagged their tails. They woofed when we left. The house also did not smell of pet.
Yet in the news yesterday a young man was attacked by 5 and luckily a passing motorist yelled for him to get into his car. He got 14 stitches and scratches. The owner was tracked down, dogs confiscated and will be quarantined. The owner's backyard showed evidence of fighting rings. One dog was put down at the pound because he became so aggressive with the employees and actually bit and bent one of the doors of the kennels. All boils down to how they are raised. Any pet for that manner!