Now I am a pretty big guy at 6'6", I also consider myself pretty agile and physically able.

So what I'm siting here wondering is how a 10 pound ball rolling at somebody is going to deter anything. They said it works by pendulum action, which basically translates into "this thing will move, but not like its been launched out of a cannon". The simple deterent would be to step out of the way and detain the damned thing!

Now maybe if they had a 500 pound version that looked like a mace and rolled 50 MPH they'd be in the game...