ΔE 6.3, close: similar, with a visible difference side by side. Medium Gray is a little darker, more muted, warmer than Ocean Gray 2 (RAF).
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Medium Gray is a little darker, more muted, warmer than Ocean Gray 2 (RAF).
The same difference applies the other way round: Ocean Gray 2 (RAF) is a little lighter, more saturated, cooler.
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 Gray 2 (RAF) on the colour wheel See Medium Gray on the colour wheel
All matches: Ocean Gray 2 (RAF) equivalents · Medium Gray equivalents