I ran accross this today while surfing MSFN
This is a very good read here and useful incase you run past your 30 day limit on your bench. It also has a guide to make your Win 7 Ultimate ISO install any version of Win 7.
You must have your own keys tho in the end so no key hacking here
http://windowssecrets.com/2009/08/20...e-for-120-days
There's an easy way to stretch Windows 7's 30-day free-trial period to 120 days so you can determine whether Microsoft's new operating system meets your needs.