Speed Yellow vs Fluorescent Yellow

How close are they?

ΔE 8.9, close: similar, with a visible difference side by side. Fluorescent Yellow is more muted than Speed Yellow.

Can I use Fluorescent Yellow instead of Speed Yellow?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Fluorescent Yellow is more muted than Speed Yellow.

Can I use Speed Yellow instead of Fluorescent Yellow?

The same difference applies the other way round: Speed Yellow is more saturated.

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.