ΔE 6.9, close: similar, with a visible difference side by side. Banshee Brown is more muted, warmer than Reddish Black.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Banshee Brown is more muted, warmer than Reddish Black.
The same difference applies the other way round: Reddish Black is more saturated, cooler.
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 Reddish Black on the colour wheel See Banshee Brown on the colour wheel
All matches: Reddish Black equivalents · Banshee Brown equivalents