Depends; has LibreOffice gained any features since the fork? I've had to use it on and off at my previous job and the experience was pretty poor, it ran slowly, dated UI, etc.
The fork happened in 2011, 11 years ago, so there are 11 years of refinement and new features. OpenOffice is in maintenance mode so there are no new features, only bug fixes.
One of the biggest features of LibreOffice over OpenOffice is compatibility with Microsoft Office files.
OpenOffice can open Microsoft Office files but doesn't support as many features as LibreOffice does.
OpenOffice can't save in the newer Microsoft Office formats (docx, xlsx, etc) but LibreOffice can.
Also, LibreOffice now has a ribbon-like interface. To enable it, click View > User Interface and choose Tabbed.
