ΔE 6.7, close: similar, with a visible difference side by side. Medium Sea Grey is more muted than Ocean Grey.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Medium Sea Grey is more muted than Ocean Grey.
The same difference applies the other way round: Ocean Grey is 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 Ocean Grey on the colour wheel See Medium Sea Grey on the colour wheel
All matches: Ocean Grey equivalents · Medium Sea Grey equivalents