Bubble White vs Glacier Blue

How close are they?

ΔE 7.7, close: similar, with a visible difference side by side. Glacier Blue is a little lighter, more saturated than Bubble White.

Can I use Glacier Blue instead of Bubble White?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Glacier Blue is a little lighter, more saturated than Bubble White.

Can I use Bubble White instead of Glacier Blue?

The same difference applies the other way round: Bubble White is a little darker, more muted.

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.