Buffalo's DriveStation Quattro is an external hard disk that consists of four 250GB PATA disks configured, by default, as a RAID 0 array providing 930GB of formatted storage. It can also be configured as a RAID 1 or RAID 5 array using the bundled utility program.
As a RAID 1 array, the Quattro would provide only 465GB of storage space, since it uses two disks to mirror the contents of the other two disks automatically, providing an up-to-date backup in the event of a hard disk failure. When configured as a RAID 5 array, the Quattro provides 698GB of storage space. If a single disk fails, your data remains safe.
The Quattro connects to your computer using USB or eSATA. It was one of the fastest external disks we've seen when connected using eSATA and set up as RAID 0 or RAID 1. Configured as RAID 0, it wrote large files at 51.52MB/s and read them at 65.07MB/s. It wrote small files at 13.24MB/s and read them at 14.85MB/s. It was a bit slower in all our tests, apart from reading small files, when configured as RAID 1. It wrote large files at 40.88MB/s and read them at 57.06MB/s. It wrote small files at 9.53MB/s and read them at 16.12MB/s.
The Quatto was much slower writing files when configured as RAID 5, although it was still quick at reading them. It wrote large files at 35.77MB/s and read them at 68.24MB/s. It wrote small files at 2.26MB/s and read them at 14.84MB/s. As expected, the Quattro copied files more slowly when connected using USB instead of eSATA. Overall, compared to other USB hard disks we've seen, the Quattro was fast at reading files but slower than average at writing them.
The difference between RAID 0 and RAID 1 file transfer speeds wasn't as great over USB as over eSATA. As a RAID 0 array, it wrote large files at 22.68MB/s and read them at 29.95MB/s. It wrote small files at 9.59MB/s and read them at 10.87MB/s. As a RAID 1 array, it wrote large files at 22.37MB/s and read them at 29.57MB/s. It wrote small files at 8.09MB/s and read them at 11.55MB/s. But it performed just as poorly over USB as it did over eSATA when writing files when configured as RAID 5, although it read files quickly. It wrote large files at 18.44MB/s and read them at 29.30MB/s. It wrote small files at 2.04MB/s and read them at 9.36MB/s.
Although you won't be in breach of Buffalo's warranty if you decide to replace a hard disk yourself in the event of a failure, this is easier said than done. The sturdy metal case is very tricky to open and disassemble.
We liked the Quattro's extensive RAID support, although you'll have to use it over eSATA to get the fastest file transfer times and, even then, the RAID 5 write speeds were disappointingly slow. The Quattro is also fairly expensive at 36p per gigabyte, but it may be worth the expense if your computer can't house an internal RAID array.
System Specifications
1TB capacity, 930GB formatted capacity (RAID 0), 4x 250GB hard disks, eSATA, USB Hi-Speed
Author: Alan Lu
Computer Shopper Online