Interesting find - this must be an "Undocumented feature" or "BUG".
This behavior does not make sense and the transform value seems to be sort of "random".
I have figured a possible workaround;
Just after the import - while all imported objects are still selected - open the XML editor (Shift + Ctrl + X)
Highlight the transform values - press Delete
- click Set (or Ctrl + Enter
) and your imported pieces will be back in their original position.