ΔE 35.0, loose: different enough that you should pick on purpose. Fire Red is noticeably darker, more muted, warmer than Volupus Pink. They are different kinds of paint: Citadel Volupus Pink is a one-coat contrast-style paint and Reaper Fire Red is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 35). Fire Red is noticeably darker, more muted, warmer than Volupus Pink. They are different kinds of paint.
The same difference applies the other way round: Volupus Pink is noticeably lighter, 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.
See Volupus Pink on the colour wheel See Fire Red on the colour wheel
All matches: Volupus Pink equivalents · Fire Red equivalents