Well, I just stated that F-15 AI is easy to defeat because it shoots 1 missile! And human F-15 pilots usually win because it shoots more then one missile!
In other words, human F-15 pilots uses F-15 advatage of having more active missiles! What is wrong with that statement?
F-15 is technologicaly more advanced then Su-27! End of story!
I don't know how active radar missiles work in real life and therefore I can not say if they are modeled corectly or not in Lock On.