ΔE 7.4, close: similar, with a visible difference side by side. Speed Metal is a little darker, more saturated than Plate Mail Metal.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Speed Metal is a little darker, more saturated than Plate Mail Metal.
The same difference applies the other way round: Plate Mail Metal is a little lighter, 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 Plate Mail Metal on the colour wheel See Speed Metal on the colour wheel
All matches: Plate Mail Metal equivalents · Speed Metal equivalents