ΔE 10.0, close: similar, with a visible difference side by side. AMT-7 Greyish Blue is a little darker, more saturated, cooler than Space Grey.
Usually, if you are not matching paint already on the model. Close match (ΔE 10). AMT-7 Greyish Blue is a little darker, more saturated, cooler than Space Grey.
The same difference applies the other way round: Space Grey is a little lighter, more muted, warmer.
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 Space Grey on the colour wheel See AMT-7 Greyish Blue on the colour wheel
All matches: Space Grey equivalents · AMT-7 Greyish Blue equivalents