Uniform Grey vs Coldstone Grey

How close are they?

ΔE 8.3, close: similar, with a visible difference side by side. Coldstone Grey is a little darker, more muted than Uniform Grey.

Can I use Coldstone Grey instead of Uniform Grey?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Coldstone Grey is a little darker, more muted than Uniform Grey.

Can I use Uniform Grey instead of Coldstone Grey?

The same difference applies the other way round: Uniform Grey is a little lighter, 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.