ΔE 17.6, loose: different enough that you should pick on purpose. Bright Warm Grey is a little lighter, much more muted than Mid Imperial Khaki.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Bright Warm Grey is a little lighter, much more muted than Mid Imperial Khaki.
The same difference applies the other way round: Mid Imperial Khaki is a little darker, 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.
See Mid Imperial Khaki on the colour wheel See Bright Warm Grey on the colour wheel
All matches: Mid Imperial Khaki equivalents · Bright Warm Grey equivalents