"The "only one" is referring to the special abilities, otherwise 5 stealth armors would make the ship utterly, permanently immune to most scanners .... and provide more defensive % benefit than an ECM module.
Scattering armor, IIRC, similarly doesn't stack it's special abilities. Nor emissive armor, apparently."
Ah yes, but remember also, the defense bonus DOES stack, add the Stealth Armor, Scattering Armor and ECM together and you get one tough ship!
