Just FYI,
I found with the default SU style settings and Vector a view-port in LO, the exported DWG/DXF would have hidden geometry show up. I even found that the exported PDF, would export this geometry as white line work that you could not readily see but was none the less there, making the files much larger than they needed to be.
After playing with styles, I found settings that would not export the hidden geometry helping produce cleaner DWG/DXFs for the consultants I work with.
Here is where I posted that information: