I no longer write for Writers' Research Group, and yet I recommend them to newbies trying to land their first online writing gigs. In general, I think the drawbacks of writing for any content company outweigh the benefits for established freelance writers. However, writing for a content company can be a godsend for a new freelancer and a great way to learn the ropes of online writing.
Writers' Research Group is essentially a middle man, contracting with new and established websites for writing and editing services, which they then outsource to freelance writers. The writers are not employees, but independent contractors. Writer's Research Group has its own small staff, including the company founders, and hires freelance editors as well as the writers.
Because of the overhead involved, writers make less per article writing through the contracting company than if they wrote directly for the websites. For example, if Writer's Research Group is paid $25 per article, they may pay their contracted writers $10 apiece. And yet, there are no employee benefits, such as health care or 401ks, because writers are essentially sub-contractors.
Another aspect to consider is the non-compete clause in Writers' Research Group's contract. If you write for them, you can't write for any of their clients within a one-year period after you end your contract.
Since there is an initial difficulty in establishing a good client base, new freelance writers might consider working for WRG. It's a great way to gain experience and learn the ropes of online writing. And you're virtually guaranteed steady work (even more than you can handle) when they are writing for a large contract.
However, if you have experience as a writer, I'd recommend looking elsewhere or consider writing directly for the websites. Case in point: I make $30 per article that I write for a new health-related site; Writers' Research Group writers are paid $10 each article. An article I would have sold to Writers' Research Group for $11 has earned over $150 on eHow. I've flown the coop, and I'm not looking back.