It depends on the "structure" of your deal with the recruiter. Contract to hire/contract they are literally a leach that will take money out of your paycheck. Also with both of these types the company you are actually on-site for doing work may not know how much you are getting paid. They are paying recruiting company something and expecting you are being paid fairly by the recruiting company. In contract to hire and contract I find that the incentives for all 3 parties (you dev / recruiting company/end client) are not properly aligned.
All that said I have worked a few contracts with recruiters and it has helped build my resume. One of the jobs I truly would have never been able to get an interview on my own. The company only uses recruiters so they do not have to hire internal hr/recruiting staff.
There are pro's and con's to working with recruiters however what annoys me most is the lack of transparency the recruiters show to us the developers. They are brokers and a fair deal is one where all sides have all the facts and can make an informed decision. I do respect truthful honest recruiters and see their purpose in the marketplace the others not so much.
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