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I gave Workshare Compare such a high rating because I don't think I could do my job without it. It has just become so integral to my workflow, that if I were to ever change jobs I think I would have to insist my new employer to me a license. It is fast and just works 99% of the time. It is very rare that it gives me errors, and when it does it's likely because the underlying document is corrupted, not because of any issues with Workshare Compare.