We pay substantially less and they can do substantially more. No bureaucracies, red tape, or idiots in Washington to tell them how to do it right. Makes an incredibly more efficient force. Good example is Sierra Leone and Executive Outcomes. The UN decided to ban PMC's after they were embarrassed by their (NATO's) ineffectiveness and EO kicking butt with minimal forces. They inserted NATO troops and the country was overrun again in months. Blood Diamonds anyone? Brought to you courtesy of NATO. Sierra Leone Civil War - Wikipedia, the free encyclopedia
A very good unbiased documentry is "Shadow Comapany". Excellent if you want to understand PMC's history and current state. Shadow Company ? Iraq War Documentary Movie, Award Winning Film about Private Military / Security Company voiced By Gerard Butler