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1. Minus superscripts for UNITS (so 's^-1' here—not 'e-3', which is fine) are converted to hyphens with the 'text' unit alternative (with the default 'mathematics' unit alternative everything is fine):
2. The times symbol between the number and the 10^-3 (e-3) is incorrectly spaced (as an ordinary math atom instead of a binary math atom) so doesn't look good.
Maybe Hans could change
\def\digitstimessymbol{\times}
to
\def\digitstimessymbol{\ifmmode\times\else${}\times{}$\fi}