Re: Whats the difference?
Yay & nay.
Imagine that document you typed in your home yesterday night, that one that took you two hours to redact. Yes, the one you needed to bring to that meeting with your boss and an important customer.
Imagine O365 stops working before the meeting.
I know, you are knowledgeable in IT and would make a local copy in a thumbdrive, but most users are not knowledgeable in IT, and MS describing their cloudy solutions as almost infallible doesn't help here either.