You'll spend about the same amount of money on either site. But you'll note you'll probably get freelancers who are better "at their stuff" on upwork because all freelancers take tests, something which will make it easier for someone who is outsourcing work to find freelancers who not only promise they can do something well but have also proved, by passing a test, that they can.
Freelancer is different because they charge their freelancers for taking and because of that most don't take any tests.
Having worked on both sites as a Freelancer I'd recommend upwork.
Upwork is costly to get someone but there are great resource/skilled freelancers. Freelancers.com is cheaper but sucks in terms of its policies. Payment policies, commission policies, hourly contract policies.
I have not personally tried UpWork, but I have to say that if it can be better than Freelancer than it is worth a shot. I have had some bad experiences on Freelancer and it is just way too much hassle for me, in my opinion, and I would just rather avoid it. I would like to see a program that really can build off of it though, and so maybe UpWork will have something to add. I am curious to see what others have to say.
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