The easiest solution to create Windows 8 USB media for the consumer would be the
Install Windows 8 button on the page Upgrade to Windows 8 with only a product key. This link runs the installer for Windows 8 directly and can create optical or USB media.
The Windows 7 USB/DVD Download tool is a close second, but requires access to an ISO file which the above button does not. I use it in exactly the same way you described when I need to quickly test a new operating system, with a big folder with all my installs on it so I can just go from one thing to the next.
MDT is a better solution for an operating system you will need to install more than once. For example, in my test lab if I need a Windows 8 system, or a Windows 8.1 Professional system, or a Windows 7 Enterprise system, etc., I can just roll out the operating system complete with standard apps to any of my virtual machines or physical machines and be ready to go, no media, just over the network. I can also polish that same image up to roll out to production machines if necessary just by a few tweaks to a task sequence.
Brandon
Windows Outreach Team- IT Pro
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