This has been bugging me since the first Arma...
M4A1's in Arma2 feature the ACOG TA01NSN, however.. this optic features Tritium for night illumination, which does not show up in Arma2 or Arma
M16A4's in Arma2 feature the ACOG TA31F (Technically since this game features USMC soldiers, it should be a TA31RCO-A4CP) However it should also use the correct reticle. Instead it currently uses the same reticle as the TA01NSN.
Since the modellers went through the trouble of constructing these two different ACOG designs, may I suggest using the correct reticles for these with day and night artwork? Below I have supplied reference images from Trijicon's website displaying the correct optics and reticles for both ACOG models currently featured in Arma2.
TA31F ACOG with Fiber Optic - Featured on the M16A4
TA01NSN ACOG without Fiber Optic - Featured on the M4A1