Real World Labs recently posted a review of the Qnap TurboNAS TS-870U-RP Rackmount, a high-end eight bay NAS server intended for use by small or medium businesses.
The review over at Real World Labs includes quite a few performance benchmarks, including simplified graphs comparing the 870U to other similar NAS enclosures for easy side-by-side comparison, so if you're interested in expanding your business's storage capacity you might want to check out the full review.
Overall Real World Labs' impression of the 870U is positive, though they do mention some issues with the unit's network interface. From their summary:
With the 870U-RP being our first of what I hope to be many we have the chance to test here at RWL in the High End SMB market.
Performance of this NAS was on par with what I expected, that is to say with dual Gbit LAN a NAS can only push so much data. Alas we did hit 118 MB/s Read and 119 MB/s Write and it's clear that these results are being compromised by the standard network interface, which is a pair of GbE connections.
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Fill testing on this unit proved to be no match, where previous units did slow down slightly this 870U-RP pushed on without sacrificing performance. A feature that we were not able to test on this unit is the 10Gbe capability and is the main feature of this NAS. With similar 10GbE capable NAS appliances selling for 400-500USD more, Qnap has released a low cost solution that is sure to grab a lot of attention.