I assume you meant laminated vs reinforced ballistic panel.
The difference is not in the mods you were looking at, but rather in the base resistances they offer. The former increases only the damage threshold part - which benefits mostly the anti-bullet bonus (+100% to damage threshold), while the latter increases only the damage resistance part - which increases the all around defensive capabilities of the armor regardless of the type of attack.
Hope I managed to clear that up for you.