Here is an illustration of my biggest concern about "bully type" dogs. They have been bred to offer less body language and warnings when they are considering a bite.
This Dogo shows calm, friendly body language while being petted...right up until he doesn't. His warning signs happen so fast that the human doesn't have time to react.
Watch this in slower motion: screen shots. These three frames all happen *within the same second*- second #23, seen in the lower left corner of the media player.
In comparison, when this police German shepherd, a more natural dog, bites, he gives plenty of warning and--if you're dog-savvy and paying attention--you know what's coming before it happens.
