I concur with WRT that a person need to know about the culture , have fluency and better English skills than the native and solid education which you silently mention it. But the bottom line is the level of education the person is having.Yes you may be fluent and have a well structured research but i think in most cases the content of the research matters a lot and is the difference of obtaining marks in school. A paper written by third world person without proper education will obviously get an F , 1. because of low quality english and the argument content in the research paper 2. Similarly a high school drop out/college drop out or a dull student/graduate in US,UK or Australia will write a well structured paper in English but the argument will be very poor and subsequently get an F. But what about a paper written by an educated ESL writer experienced and fluent in english? He will have a well discussed paper and proper languange structure.
I feel that it is lying and cheating when students are told that the papers are written by Native English Writers who are educated but it happens that most of the "native english Writers" happen to be drop outs and failures from instituions. That would be a scam because the english would be good but the content and argument of a high school kid. I wonder how a person would be arguing a technical subject or a research project involving application ,guess work i think?? Maybe some sites fall under this category in native english countries.
Pheelkys: Have you checked the number of foreigners in US,UK and Australia universities? Do you have their statistics? Maybe you would wish to know their numbers. And where do you think these thousands and thousands every year go after their visa expires, back in their country where jobs sometimes its hell to get. I have been across some parts of Africa and Asia and meet with tens and tens of western educated students who are jobless and working on even less than $15 a day!! Don't you think that person will write for $4 a page if he can write 10 pages a day he will be better off and write an excellent research paper 10 times better than a college drop out or a failure in "English native countries". Blame the scam sites for exploiting and misusing the labour and sometimes encouraging uneducated folks from those countries, but i don't think it will be evil to get an educated guy in developing world who can write better and cheaper, its economics and business. The same applies to sites owned by native english guys but who are not educated enough, they cheat and lie to their clients too.