Khaki Highlight vs Silver Grey

How close are they?

ΔE 8.9, close: similar, with a visible difference side by side. Silver Grey is more muted, warmer than Khaki Highlight.

Can I use Silver Grey instead of Khaki Highlight?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Silver Grey is more muted, warmer than Khaki Highlight.

Can I use Khaki Highlight instead of Silver Grey?

The same difference applies the other way round: Khaki Highlight is more saturated, 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.