ΔE 8.9, close: similar, with a visible difference side by side. Insignia White is a little darker, cooler than White Sands.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Insignia White is a little darker, cooler than White Sands.
The same difference applies the other way round: White Sands is a little lighter, 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 White Sands on the colour wheel See Insignia White on the colour wheel
All matches: White Sands equivalents · Insignia White equivalents