I went through the process of ordering the $40 upgrade offer via the Internet. I choose not to install Windows at this time, but to create the .ISO file (I’ll have more on this later) and everything went fine as the .ISO file (Windows.iso) was created on my disk drive.
Next I used the .ISO file to create a bootable installation DVD using a free software product named ImageBurn.
I then installed Windows 8 using the bootable DVD I had just created on an unformatted hard drive with the Cat6 Internet connection disabled as I wanted to see if the installation would complete, which it did (you still need to enter the product key, but this came as no surprise).
The big surprise is that Windows 8 booted straight away to the “Desktop” and not the “Start”/Tiles mode (Formerly know as the Metro screen). I rebooted and again the Desktop was displayed. I then went to the Start/Tiles screen and rebooted from with this screen and once again Windows 8 went straight to the Desktop.
The computer I used to order and download the .ISO file was running Windows 7 Professional 64Bit. What was installed using the .ISO was Windows 8 Pro 64Bit.
What I can tell you is that the hash value of the .ISO file does not match the hash value of a TechNet or MSDN .ISO file. One big reason for this is that install.wim file on a TechNet bootable DVD is replaced with an install.esd on the upgrade offer bootable DVD.