The differences between our test candidates could not have been greater. The portable hard drive from Transcend, like Fujitsu's HandyDrives, appear tiny when put alongside WiebeTech's DuoGB or the two monsters from Maxtor and Western Digital.

The RocketMate housings from HighPoint are exactly size-wise. In performance terms, they outclass the competition since they are equipped with the quickest UltraATA hard drives and the SATA connection.

Fujitsu and Transcend do not place strong speed constraints on the hard drives in their systems since both USB 2.0 and Firewire 400 supply enough performance for 2.5" hard drives. This is shown by the stepped pattern on the transfer chart. If there were a bottleneck at the interface, you would see a level line - like on the Maxtor and Western Digital models.

As far as these hard-drive manufacturers' external solutions are concerned, Maxtor makes an excellent showing that is even more suitable for backups. You can start the entire process swiftly using OneTouch. Western Digital, on the other hand, offers a shade better performance and the largest overall capacity.

If you who want to save hundreds of gigabytes relatively portably, you'll need the solution offered by the DuoGB from Wiebetech. It offers enormous capacity on demand and spares you the trouble of moving your whole computer. There are no other affordable alternatives in this capacity class.

The underdog, going by the name of e.SATA from HighPoint, actually won us over. While the Rocket 1511 interface card with just one external port is pretty pointless, the RocketRAID 1542 offers good flexibility with two internal and two external ports.

e.SATA makes real sense, however, when one or two serial ATA ports are already available. Then all you need to do is buy an adapter cable and a RocketMate housing (HighPoint B11 or B22) in order to run any kind of hard drives with an UltraATA/133 or UltraATA/100 interface. Although the adapters and RocketMate are not more expensive than buying the hard-drive housing for USB and/or Firewire individually, performance is clearly higher.

The only fly in the ointment is that e.SATA is as yet only being marketed by HighPoint. Merely the fact that standardized cables are used cannot guarantee success at this moment in time - even when its overall stellar performance is taken into account. That's because Firewire 800 is a dangerous rival and PCI Express also enables external connection of high-speed components.