Crusted Sore vs Russet

How close are they?

ΔE 7.1, close: similar, with a visible difference side by side. Russet is a little lighter, more saturated, warmer than Crusted Sore.

Can I use Russet instead of Crusted Sore?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). Russet is a little lighter, more saturated, warmer than Crusted Sore.

Can I use Crusted Sore instead of Russet?

The same difference applies the other way round: Crusted Sore is a little darker, more muted, cooler.

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.