ΔE 10.4, fair: the same colour family, but not a straight swap. AMT-12 Dark Grey is more muted than Dark Reaper.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). AMT-12 Dark Grey is more muted than Dark Reaper.
The same difference applies the other way round: Dark Reaper is more saturated.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Dark Reaper on the colour wheel See AMT-12 Dark Grey on the colour wheel
All matches: Dark Reaper equivalents · AMT-12 Dark Grey equivalents