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The TVS-EC1080 is a better option than TVS-871T for processing, as it is cheaper and supports RAID10. Maximize the meory, and add the SSD mSATA cache drive. You probably need to use the QNAP SSD, but you should be able to use any memory. Look for specs at http://shop.qnap.com/.
TVS-871T with RAID6 is a good archive option.
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