I started using OpenOffice a couple decades ago when I got tired of pirating the market leader. Not wanting to start any religious wars, but I still haven't made the leap to Libre.
It's also worrying that The Apache Foundation continues to promote and distribute OpenOffice despite unfixed security issues and zero updates to the software. So many people in the FOSS world have called on them to finally retire it, put it in the Attic and keep up a good reputation for FOSS - but they won't do it. It still gets hundreds of thousands of downloads despite being unfixed.
It's irresponsible of The ASF IMO.
https://www.openoffice.org/press/2.0/press_release.html (2005-10-20)
https://news.microsoft.com/2005/11/21/qa-microsoft-co-sponso... (2005-11-21)
By choosing OpenOffice, you should be aware that you are at an increased risk for attacks. One of the consistent problems with OpenOffice over the past years has been that they have often not published security fixes for many months, sometimes critical ones, for vulnerabilities that were publicly known.
(Due to the shared codebase, obviously, many security issues affect both LO/OO, yet, with the difference that LO usually fixes them in a timely manner.)