ΔE 6.2, close: similar, with a visible difference side by side. Dark Grey is a little darker than Deep Rusto.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Dark Grey is a little darker than Deep Rusto.
The same difference applies the other way round: Deep Rusto is a little lighter.
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 Deep Rusto on the colour wheel See Dark Grey on the colour wheel
All matches: Deep Rusto equivalents · Dark Grey equivalents