I’ve found OnlyOffice to have bettet interoperability with MS Office, than LibreOffice. Not perfect, but things like layout are better transferred between the programs. If that is a main concern (i.e. you frequently collaborate with people using MS Office), that would be a good solution. There is however some sketchy licensing stuff going on with OnlyOffice I have yet not fully understood.
It seems Calligra can open, but not save in MS Office file formats. I guess MS Office can open OpenDocument-files, but I believe interoperability will not be too good. Again, if that is a main concern. For me now, it is not.
I’ve found OnlyOffice to have bettet interoperability with MS Office, than LibreOffice. Not perfect, but things like layout are better transferred between the programs. If that is a main concern (i.e. you frequently collaborate with people using MS Office), that would be a good solution. There is however some sketchy licensing stuff going on with OnlyOffice I have yet not fully understood.
It seems Calligra can open, but not save in MS Office file formats. I guess MS Office can open OpenDocument-files, but I believe interoperability will not be too good. Again, if that is a main concern. For me now, it is not.