ΔE 6.5, close: similar, with a visible difference side by side. Medium Gray is a little lighter than Bluish Grey.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Medium Gray is a little lighter than Bluish Grey.
The same difference applies the other way round: Bluish Grey is a little darker.
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 Bluish Grey on the colour wheel See Medium Gray on the colour wheel
All matches: Bluish Grey equivalents · Medium Gray equivalents