ΔE 9.3, close: similar, with a visible difference side by side. Faded P.R.U. Blue is a little lighter, more saturated than Regiment Grey.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Faded P.R.U. Blue is a little lighter, more saturated than Regiment Grey.
The same difference applies the other way round: Regiment Grey 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.
See Regiment Grey on the colour wheel See Faded P.R.U. Blue on the colour wheel
All matches: Regiment Grey equivalents · Faded P.R.U. Blue equivalents