I can't imagine running O-365 on NMCI. I have to use it at my work with regular cable internet (and a VPN, which slows down things a little). Outlook is miserable to use, even on IE. It's extremely laggy. I used to be able to use the Outlook app on the computer, but supposedly we don't have a license for that now, according to IT (which are little help in general). And why can't I mark something as "UNREAD" from within the email? Why do I have to go back to the email list and then right click to do that? It's so annoying. I don't have to do that on my phone or in the actual Outlook desktop app.
I'll occassionally have to use 365 Office to update something on our Sharepoint, which quickly devolves into me just wishing I had downloaded the document, updating, and then upload it back.
Our work computer has plenty of resources, so it's not that. I run into the same lagginess on my home PC or my Macbook Pro.