There's very little evidence of their hybrid rocket motor being safer than liquid fueled engines. An accident at the Scaled Composites plant killed 3 people and

There's very little evidence of their hybrid rocket motor being safer than liquid fueled engines. An accident at the Scaled Composites plant killed 3 people and severely injured several others during a test of the rocket system, for example. Also, liquid rockets are not particularly prone to "go boom", the most likely failure scenario is a loss of control, but that can happen to any rocket.