Macrium Reflect installation

I want to backup my Win 7 OS as I just had a hard drive failure. I have been advised to use the above mentioned software to do so. Their instructions say to format the drive b/f installing their software. Has anyone used this software or can WD software backup the Win 7 OS –

The drive is pre-formatted. It comes with a basic backup software. You can also download a simplified version of Acronis True Image from WD, which makes an image backup of the drive, whereas the standard backup software backs up just most files, but not the full Windows system.