Bzz Agent & Influenster?

Has anyone used BzzAgent or influenster?I've heard good things about both, but I'm most involved in influenster. BzzAgent is a site where you write reviews for products that they send to you. Influenster is supposed to be similar. Which one is best? What did you think? I got an account and am still awaiting an invitation for both.
              vs.   


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