Sybarite Green vs Gnarls Green

How close are they?

ΔE 22.0, loose: different enough that you should pick on purpose. Gnarls Green is noticeably darker, warmer than Sybarite Green.

Can I use Gnarls Green instead of Sybarite Green?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 22). Gnarls Green is noticeably darker, warmer than Sybarite Green.

Can I use Sybarite Green instead of Gnarls Green?

The same difference applies the other way round: Sybarite Green is noticeably lighter, 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.