Aged Hide vs Martian Orange

How close are they?

ΔE 21.7, loose: different enough that you should pick on purpose. Martian Orange is noticeably darker, much more saturated than Aged Hide.

Can I use Martian Orange instead of Aged Hide?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 22). Martian Orange is noticeably darker, much more saturated than Aged Hide.

Can I use Aged Hide instead of Martian Orange?

The same difference applies the other way round: Aged Hide is noticeably lighter, much more muted.

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.