No, the only issue I had was that when a plugin is available in the 32 bit version but not the 64 bit version, if you open the 64 bit version the 32 bit version will lose the plugin’s pane from its layout (because the layout is shared). On Windows you can run both at once, but starting a new scene will wipe the cached .tdl files and renders from the temp folder (which is shared) so that renders in the other version will fail. You do need to make sure that if you upgrade one to a new point version you upgrade the other too.