Red Cloak vs Seraph Red

How close are they?

ΔE 17.4, loose: different enough that you should pick on purpose. Seraph Red is noticeably darker, much more muted than Red Cloak.

Can I use Seraph Red instead of Red Cloak?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Seraph Red is noticeably darker, much more muted than Red Cloak.

Can I use Red Cloak instead of Seraph Red?

The same difference applies the other way round: Red Cloak is noticeably lighter, much 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.