Do you understand what it means to be factually incorrect? This isn't a matter of opinion, the argument you presented is demonstrably wrong.
http://uk.reuters.com/article/2013/11/05/uk-britain-migrants-idUKBRE9A40MD20131105
"If you look at those immigrants who came after 1999, both EA (Euro Area) and non-EA immigrants have made a positive fiscal contribution," Christian Dustmann, co-author of the report from University College London, told Reuters.
"Over the same period, native-born individuals basically took more out of the welfare system than they put in, in terms of taxes."