Vista Home Premium OEM discs say they can only be installed on one system. Does that mean only one time, so i would never be able to reinstall it on that system again if i reformat? heres the disclamer "This OEM software is intended for system builders only and cannot be transferred to another PC once it is installed. The purchaser of this software is required to comply with the terms of the System Builder license, including the responsibility of providing all end user support for the software." Should i just spend the extra $100 for the normal version? I still get to use updates right?