The savings are the big thing with that. I could live the rest of my life without working for less than half than one of those missiles costs. I have heard that they are safer for the user too because they don't have to store explosives on the ship.
This is an issue I have a problem with in movies where some superhero or monster or whatever gets shot with all our weapons without taking dammage. I have to call bs there. If you hit something hard enough, it will break.