ΔE 9.6, close: similar, with a visible difference side by side. Steel Legion Drab is a little darker, more saturated than RAF Dark Green.
Usually, if you are not matching paint already on the model. Close match (ΔE 10). Steel Legion Drab is a little darker, more saturated than RAF Dark Green.
The same difference applies the other way round: RAF Dark Green is a little lighter, more muted.
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 RAF Dark Green on the colour wheel See Steel Legion Drab on the colour wheel
All matches: RAF Dark Green equivalents · Steel Legion Drab equivalents