The reason for the high speed is that the RecImg Manager restore image only includes the OS and settings so it's much faster to recover your system than with a normal restore image which includes the aforementioned virtual kitchen sink.

But "hold hard!" you might be saying, "doesn't Windows 8 have something called 'Refresh' ... or is it 'Reset'? ... that does much the same thing?"

Windows 8, in common with every version of Windows since XP, has the ability to create Restore Points that take you back to a freshly installed system (in the PC Settings Panel, it is now called "Reset Your PC" just to confuse the unwary). Should you reset your Windows 8 PC you will be going back to square one, as if you had never used your PC. Ever. It is unlikely, in most cases, that this will be what you want.

The PC Settings Panel also has a "Refresh" function that restores your PC system settings to default and removes all of the installed from third-party sources ... the latter being what creates a huge sucking time sink.

Windows 8 does also have a command line utility called RecImg which lets you create a custom Windows 8 "Refresh Point" in Windows Installer Image format. Using this WIM file, you can restore your PC to a specific previous state which can include personalized Windows settings, desktop applications with saved preferences and so on. Very nice.