All our products come with 6 activations. How you use them, either to install on multiple PC's, or to make hardware upgrades to the same one, is entirely up to you.
And of course, with the ability to DEACTIVATE a product (which will reclaim its activation for that PC) when you don't need to use a PC anymore, you have complete freedom to install everywhere.
The only thing not allowed, is to share a license with other people. So, it's ok to install into up to 6 computers at the same time, but they must all belong to you.