USAFRet :
Not trying to argue here, but using a VM as a backup seems to me to be a waste of time. An image, sure. A VM? Not so much.
An image does no good if the information you forgot to transfer over is within a program. e.g. One of the people whose computer I helped upgrade realized a week later that she didn't know her Evernote username and password. She'd set it up years ago, set it to remember her login info, and completely forgotten it.
If all she had was a backup image, she'd have had to get her old computer back from the charity she donated it to, restore the image, start up the computer, start up Evernote so she could see her username, then initiate a password recovery.
But I had set her up with a VM of her old computer. So all she had to do was start the VM, start up Evernote, and get her username from there.
Another example is my brother in law. When he upgraded from a Macbook to a PC laptop, I copied all his data files over for him. 6 months later he needed a file which had been on the Macbook, but couldn't find it in the 60 GB of files I'd copied over. He didn't remember the filename and had no idea where it was within the directory structure of all the files I'd copied over, but he remembered exactly how to get to the file on the Macbook using the program which generated the file.
Unfortunately, the Macbook had been reformatted and was on the other side of the country being used by a relative. Fortunately I'd also converted his Macbook into a VM. He fired it up, started up the program, and 2 minutes later he found the file he needed.