We’ve praised SOS in the past for its potent combination of business-friendly features, power-user options and excellent ease of use, and all that still stands.

From the splash screen you can instantly choose whether to store or recover files, either online or offline, while a simple five-step wizard takes you through the basics of configuring and scheduling backups.

You can switch on email notifiers and a gauge at the bottom tells you how much space your backup will need: exceed your current plan and you’re prompted to upgrade.

Expert users can switch instantly to classic view that allows you to switch between backup and restore tabs.

Features are strong, with the program archiving daily versions of files, offering drag-and-drop support and the most responsive live protection of any service on test: it picks up changes within seconds of them being made and uploads only the changed data on a bit-by-bit basis.

But you do need to select files for live protection individually, while Vista users will need to disable User Access Control to get Drag and Drop to work.

The option to provide the initial backup on a hard disk is a boon for power users, as is the ability to upload from multiple PCs.

Files are protected by 256-bit AES encryption and stored across six secure datacenters worldwide.

SOS did poorly in our speed tests, taking nearly 11 hours to complete the initial backup and three and a half hours to restore it. We also had problems with the installation of .NET Framework 1.1 (as required by the client) on Windows Vista x64. These factors just knock SOS out of serious contention.