ΔE 9.9, close: similar, with a visible difference side by side. Dark Green RLM71 is a little lighter, cooler than Muddy Brown.
Usually, if you are not matching paint already on the model. Close match (ΔE 10). Dark Green RLM71 is a little lighter, cooler than Muddy Brown.
The same difference applies the other way round: Muddy Brown is a little darker, 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 Muddy Brown on the colour wheel See Dark Green RLM71 on the colour wheel
All matches: Muddy Brown equivalents · Dark Green RLM71 equivalents