For these offers, I think you are always dealing with a VLK version of the software and it may or may not work forever. At such a low cost, I think it's worth it for most people to take the chance knowing they may have to buy it again at a later date.
I'm on Office 365 user and I think that it is a great value. That value boils down to what you need and how much you need. For me, I have multiple desktops in my house (myself, wife, son and daughter). And I have a few Mac's in the house too (myself and my daughter). Our ability to install Office on any number of devices is advantageous. Since I only need 4 of the 6 accounts, I provide one to my dad, and I still have 1 sitting around that I could give to a friend or family if i wanted to. And I get the Office 365 subscription discount vi my employer, so it's $69.99 for me t get all 6 accounts.
The real benefit for me is OneDrive. Each of those 6 accounts gets 1TB of oneDrive space. While I use my OneDrive space pretty extensively, the rest of my family really just uses it as an automatic backup location for cell phone pictures and videos. All of us have our mobile devices syncing to our 1TB onedrive accounts.
I've found no other better storage/$ cloud option that offers up to 6TB of OneDrive space for the cost of Office 365. For me, I'm willing to pay the cost of Office 365 simply for OneDrive, having Microsoft Office is just an extra bonus.