@audiophile1 "No plugs will scratch the IEC connectors"
as an experienced analog design engineer I can say this is not correct! typically product from established hi-end company chooses IEC receptacle and plug (or assembled cable) from one company (Kawasaki, Amphenol, etc), which ensures reliability and interconnect performance for decades, because interconnect is checked many times and contacts are inspected for scratches, plating surface damages etc.
wondering, if you ever looked IEC plug/rec. under microscope after experiments? Please keep in mind, after you scratch contact surface, contact resistance could dramatically increase, and then plugging “new fancy” cord will give you relief for few days.. then you need to try to “improve” sound again, by buying new PC :-)