I've had only a casual interest in guns like this, but I'm glad you described how to shoot the blamed thing!
Always kind of wondered about that.
On several occassions I've been asked to put down small animals suffering from injuries or wounds and delivered the shot to the back of the head holding a rifle pistol-style. I imagined that would be the way to shoot one of these.
As to practical, I've never turned down an invitation to shoot an odd gun of any kind.