Star Blue vs Thunderhawk Blue

How close are they?

ΔE 6.2, close: similar, with a visible difference side by side. Thunderhawk Blue is more muted, warmer than Star Blue.

Can I use Thunderhawk Blue instead of Star Blue?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Thunderhawk Blue is more muted, warmer than Star Blue.

Can I use Star Blue instead of Thunderhawk Blue?

The same difference applies the other way round: Star Blue 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.