Warm Orange vs Violent Vermillion

How close are they?

ΔE 9.0, close: similar, with a visible difference side by side. Violent Vermillion is a little lighter, cooler than Warm Orange.

Can I use Violent Vermillion instead of Warm Orange?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Violent Vermillion is a little lighter, cooler than Warm Orange.

Can I use Warm Orange instead of Violent Vermillion?

The same difference applies the other way round: Warm Orange is a little darker, 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.