Both are flawed and incredibly crappy places to live if you're pessimistic enough. Frankly I'd much rather live in the U.S. because many parts of Europe look far too crowded.
Let's face it, both suck. The planet sucks. Ignorant idiots are everywhere and there isn't a single perfect leader in the world. All governments are flawed. Any nation with decent living conditions manages to rape you of your money in one way or another.
But really, I'd much rather live in the United States. We get top priority on a lot of things including TV shows, movies, and videogames. Our currency may suck but a life of crime and deceit (and I'm talking about politics/business) will net you enough income to buy a solid gold statue and piss on it.
Unless I could live in Scandinavia, I would much prefer the U.S.
Suck it.
Ohh, and the reason Europeans aren't as fat as Americans is because we've been prospering for several decades and overdosing on the high of consumerism. Wait a few decades, and your countries will be full of fat people. Enjoy!