Axios
I just now looked at the onlyoffice website. From what I saw, and maybe I read it wrong, but it sounds like onlyoffice is an online service? For me, for privacy and peace of mind, no possible way on earth would I write nor store documents in the cloud. Heck, my important documents are typed on a computer that is not connected to any network.
I heavily rely on a word processor and spreadsheet. During a typical day of typing, Word 2010 saves me over an hour of labor as compared to LibreOffice. LO is not ideal for me, but at least LO isn't a cloud service. Humorously, I have found Geany to work well for my need of a split screen.
From what I am seeing, it appears that the biggest difference between onlyoffice and LibreOffice might be onlyoffice being an online service.