Buffalo DriveStation Quattro
It may look like a NAS device, but Buffalo's DriveStation Quattro is a 1TB, four-disk version of the company's 500GB DriveStation Duo, connecting directly to a PC rather than over the network. Aside from the two extra drive bays and the larger chassis, there are a couple of other notable improvements.
The extra disks add RAID5 to RAID0/1 and JBOD, offering a mix of capacity and redundancy. The drive comes formatted as FAT32 in a RAID5 array, but we changed that to JBOD and NTFS to get maximum capacity from the drives.
Over USB, performance proved a pleasant surprise, with a 1.6GB single file writing at over 25MB/sec, and a 1.8GB collection of MP3s in around a minute-and-a-half (13MB/sec). Copying thousands of tiny (sub-20k) files is often a problem for external hard disks, but the Quattro slowed to only 1MB/sec.
Switching to eSATA yielded even better results: a 38MB/sec write speed with our large file, falling to 18MB/sec with the MP3s and 1MB/sec with the tiny files. Switching to RAID5 saw a slight slope off in speeds - most seriously with the 11MB of tiny files, which fell to 0.06MB/sec - a standard failing of RAID5 with writes smaller than single-stripe size.
For access, the front of the unit slides off, and it's a matter of two screws to change a disk. You're confined to Parallel ATA only, and capacities will also need to match if you're using RAID. The bundled software is nothing extraordinary: SecureLock encryption to prevent people gaining unauthorised access to selected files or the whole drive, plus RAID and formatting setup utilities - none of which is currently compatible with Vista.
In terms of price per GB, there are certainly cheaper options around, but there isn't much to compete with the Quattro in terms of sheer flexibility. If you're looking for a fast workstation disk with good redundancy options, the Quattro is worth a look.
Buffalo Technology DriveStation Quattro 2.0TB (4 x 500GB) Desktop External Hard Drive FireWire Combo with TurboUSB2.0 HD-QS2.0TSU2/R5 (Black)