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I've been thinking about using prosociate to import amazon products to my niche site. But I've read on a couple of blogs that these kind of plugins hurt your rankings. Is this true or just imaginary?
I know that importing thousands of duplicate products + descriptions from amazon isn't good, but does google rank your site lower just for using such a plugin? Even if you manually write a unique description for every product?
Would love to know more about this.

Thanks!