Lazer sights help a little bit, but reflex sights are good but in a heavy fire-fight you dont have the time to even look down the sights, it is mainly point-and-pull and hope it hits something.
You are right about the rainbow six reloading system, changing magzines when you have partially emptied a mag is called a tactical reload.
Operation flash point and Arma are based of the VBS1 simulator that the military uses.