ΔE 7.1, close: similar, with a visible difference side by side. Arctic Blue (Metal.) is a little lighter than Shine Silver.
Can I use Arctic Blue (Metal.) instead of Shine Silver?
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Arctic Blue (Metal.) is a little lighter than Shine Silver.
Can I use Shine Silver instead of Arctic Blue (Metal.)?
The same difference applies the other way round: Shine Silver 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.