Dryad Brown vs Red Rage

How close are they?

ΔE 6.2, close: similar, with a visible difference side by side. Red Rage is more saturated, cooler than Dryad Brown.

Can I use Red Rage instead of Dryad Brown?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Red Rage is more saturated, cooler than Dryad Brown.

Can I use Dryad Brown instead of Red Rage?

The same difference applies the other way round: Dryad Brown is more muted, 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.