Cost, coverage, choice - some of the trade-offs needed to make a healthy nation. As the US Congress struggles to repeal and replace the Affordable Care Act - widely known as Obamacare - we ask what makes for a good healthcare system and how does society as a whole get value for money? Is it an insurance based system, like many used world wide, or is a single payer system like Britain's National Health System better and more fair? (Photo: People protesting against the repeal of the Affordable Care Act. Credit: Getty Images)