Working well, generally:

http://fortune.com/2015/09/08/germany-migrant-crisis/

>The 6.6 million people living in Germany with foreign passports paid $4,127 more in taxes and social security on average than they took in social benefits in 2012--generating a surplus of 22 billion euros that year, according to one report

More recently:

https://qz.com/901076/what-effect-did-the-record-influx-of-r...

I have no idea how that's working out for Germany. But I was under the impression that Europe gives away social benefits to the refugees (at least at the initial stage). While the author of the parent comment (I expect) is self sufficient from day 1 (otherwise, he / she wouldn't be allowed in, right?). It's not like the government of the US is spending people's taxes on him / her. He / she paid for the interview with the embassy, paid for the visa, then was paying taxes and spending money locally buying food / clothes / etc. (thus creating / supporting new jobs).