Starting with this review, we have switched to classless ranking for NASes. Below is the Ranker Performance summary for the TS3400. Note that this ranking is for all products tested and doesn't relate to a particular class of processor or number of drives. In this chart, undoubtedly the total ranking of #28 was dragged down by relatively low scores for iSCSI performance as well as Mixed Read Write scores.
Buffalo TeraStation TS3400 NAS ranker performance summary
However, you can filter the NAS Ranker by the number of drives and the processor class. Filtering for four-drive NASes shows the TS3400 ranking 10 out of 18 products. All but two of the products ranked above the Buffalo are Intel Atom based except for the Intel i5-based iXsystems Mini Plus FreeNAS and, more significantly, Synology's DS413, which is powered by a dual-core Freescale QorIQ CPU.
To see how the Buffalo ranked with other four-bay NASes using dual-core application-specific processors, I added an SoC-2 Class filter to the four drive filter and came up with the view below. You can see that there are only three products that now match.
NAS Ranker results filtered
For this filter, the TS3400 ranks second behind the Synology DS413. But if you delve a little deeper, you'll see that the TS3400 is a clear value winner in this matchup. A recent check of Amazon showed that the DS413 was selling for $499. The TS3400 was selling for $554. The big difference in value is the TS3400 price includes four 1 TB drives - the DS413 price is for a diskless 4 bay NAS.
The TS3400 is another example of Buffalo's focus in feature and performance improvement in its latest round of NASes. Unlike some of the earlier versions of TeraStations, the TS3400 has hot-swappable drives. It also supports RAID migration and RAID expansion. Rebuild times for a 4TB X 1 are reasonable, coming in at 8h 50m for RAID 5 and 7h 45m for RAID 10. There is full support for AFP, SMB, NFS and FTP. It can be used as a Time Machine target, or can be configured as an iSCSI target.
In reviewing Buffalo NASes, we've found that they generally don't deliver best-of-class performance. And compared to products from Synology, QNAP and others, they lack some features, most notably any sort of app or add-in system.
But where they excel is at value and the TS3400 is no exception. The TS3400 is one of the most cost-effective four-bay NASes available, delivering a lot of storage and decent performance for your dollar.