ΔE 7.0, close: similar, with a visible difference side by side. Thousand Sons Blue is more muted, cooler than Power Blue.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Thousand Sons Blue is more muted, cooler than Power Blue.
The same difference applies the other way round: Power Blue is more saturated, warmer.
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 Power Blue on the colour wheel See Thousand Sons Blue on the colour wheel
All matches: Power Blue equivalents · Thousand Sons Blue equivalents