ΔE 9.1, close: similar, with a visible difference side by side. Dark Flesh Tone is a little darker, cooler than Rust.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Dark Flesh Tone is a little darker, cooler than Rust.
The same difference applies the other way round: Rust is a little lighter, warmer.
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 Rust on the colour wheel See Dark Flesh Tone on the colour wheel
All matches: Rust equivalents · Dark Flesh Tone equivalents