Lucius Lilac vs Lustful Purple

How close are they?

ΔE 7.2, close: similar, with a visible difference side by side. Lustful Purple is a little darker, more saturated than Lucius Lilac.

Can I use Lustful Purple instead of Lucius Lilac?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). Lustful Purple is a little darker, more saturated than Lucius Lilac.

Can I use Lucius Lilac instead of Lustful Purple?

The same difference applies the other way round: Lucius Lilac is a little lighter, more muted.

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.