Golden Armour vs Heirloom Gold

How close are they?

ΔE 27.3, loose: different enough that you should pick on purpose. Heirloom Gold is noticeably lighter, much more muted, cooler than Golden Armour.

Can I use Heirloom Gold instead of Golden Armour?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 27). Heirloom Gold is noticeably lighter, much more muted, cooler than Golden Armour.

Can I use Golden Armour instead of Heirloom Gold?

The same difference applies the other way round: Golden Armour is noticeably darker, much more saturated, 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.