Squig Orange vs Orange

How close are they?

ΔE 25.2, loose: different enough that you should pick on purpose. Orange is a little lighter, much more saturated, warmer than Squig Orange.

Can I use Orange instead of Squig Orange?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 25). Orange is a little lighter, much more saturated, warmer than Squig Orange.

Can I use Squig Orange instead of Orange?

The same difference applies the other way round: Squig Orange is a little darker, much more muted, 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.