Western Digital's My Book range is dominating the external storage market and it's easy to see why. They're good-looking drives with huge capacities, reliable hardware and come at a great price.

Surprisingly, WD's latest addition to the range is somewhat Apple-centric and this is where the problems begin for PC users. It's a hard drive and so can't exclusively be for Mac use. The drive can be reformatted for Windows use, but doing this, especially for 1TB models, is a hassle that PC users could do without.

First the good news...

The Studio Edition sports a clever power-saving mode, SmartPower, which turns on and off with your PC. It's a handy feature, as is the capacity and status indicator that now takes the form of an attractive strip rather than the circle of previous models (note that this is unavailable with an eSATA connection). The drive is also very quiet for such a large drive and reasonably speedy for access. Sadly, all this good work is undone when it comes to using the back-up software.

Backup is slow, but once done we found the drive jumped straight into action again on startup and added new files. Yet after just a few days the drive refused to make more backups, simply displaying "pending" as the permanent status. We discovered that this problem is widespread with the Memeo software shipped under the WD Anywhere Backup banner.

Downloading the latest version and starting a new backup plan seemed like the answer, but again we were left with a drive that identified backups yet failed to execute them. Drives like this are designed to back up your data in case of disaster and although we had 95 per cent of what we wanted, we were still missing the most recent backups.

We expect that Memeo's flaws will be ironed out soon, but for now it's hard to recommend a paid-for service that halts on the job.