I've been running Office 2010 for, well, 8 years now. I got it when my work had some sort of corporate agreement that employees could get a full copy with just a valid corp. email. We recently switched to Office365 and while I can use that at home, that means that work would have access to my personal files. Oh HELLS TO THE NO!!!
I had recently gotten $5 Windows 10 licenses off ebay so I figured for $10 or so I should see if the Office2016 ($5) and Office365($4) keys are legit.
THEY ARE!!!! With caveats.
All of these licenses are either from the EU which has some pretty consumer friendly laws, or from resellers. I bought two different licenses just to see the differences.
First one is a 'Lifetime Office 365' license. This one worried me the most because you really are just getting an Office365 account on some random website. For example the credentials I got were for the 'myoffice365.site' domain. Really. I have an email address of *@myoffice365.site' BUT its a LEGIT 5 device Office365 account. I can even download office and use it offline, or use the apps via portal.office.com
So its a legit MS domain. Now the SHITTY part is that some random dude in Europe would be able to look at anything I save online (via sharepoint or Onedrive). So that's why I downloaded the Office apps and can save them to my PC.
The second key I bought was JUST for Office 2016. It has no link to Office365. Its only a single use so I'll probably install it on a laptop or something.. I haven't used it yet.
What if MS clamps down on these resellers? So what. My documents are on my PC and at most they could deactivate my product ID. For the $10 I spent I'm willing to take that risk.