The most telling difference, if you can see the top of the arm, is that the Chinese repro say "Singer Sewing Machine Company" rather than "Singer Manufacturing Company". Just because a company has obtained the rights to use the name Singer on their product does not make them a genuine Singer (i.e. Simanco) at least in my estimation. I have seen them on CL and ShopGoodwill (even with the manufacturers "made in china" tag plainly displayed) getting as much as a true vintage singer even though they don't have the quality.
But then, for people looking for a simple display piece, they definitely are shiny!