Went to buy the Family 3 pack of Home Premium to upgrade my older PCs. The "expert" at Best Buy told me you cannot use the WIn 7 Upgrade Disk to go from XP to Win 7. Personally I think this is bull droppings but now I'm uncertain and want confirmation. Has anyone actually done a clean install using a Win 7 Upgrade DIsk to go from XP to Win 7? Yes, I know there is not a simple upgrade option from XP to Win 7 like there is from Vista to Win 7 but it should still work as long as you are replacing a valid copy of XP. Thanks.