ΔE 11.4, fair: the same colour family, but not a straight swap. Iridescent Stainless Steel (Fine) is a little lighter, more muted than Canoptek Alloy. They are different kinds of paint: Citadel Canoptek Alloy is a metallic and Golden Iridescent Stainless Steel (Fine) is a pearl paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Iridescent Stainless Steel (Fine) is a little lighter, more muted than Canoptek Alloy. They are different kinds of paint.
The same difference applies the other way round: Canoptek Alloy is a little darker, 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.
See Canoptek Alloy on the colour wheel See Iridescent Stainless Steel (Fine) on the colour wheel
All matches: Canoptek Alloy equivalents · Iridescent Stainless Steel (Fine) equivalents