Bugman's Glow vs Kiwi Brown

How close are they?

ΔE 20.1, loose: different enough that you should pick on purpose. Kiwi Brown is a little darker, more saturated than Bugman's Glow.

Can I use Kiwi Brown instead of Bugman's Glow?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 20). Kiwi Brown is a little darker, more saturated than Bugman's Glow.

Can I use Bugman's Glow instead of Kiwi Brown?

The same difference applies the other way round: Bugman's Glow is a little lighter, 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.