What makes it really
frustrating is that it's not just about being fast - when baddies enter the scene, you can't shoot them until they stand still, and then you have some <500ms time window to shoot them.
This is extremely
annoying in are(n)a... 3? "It's a spy, shoot him!", then there's like 4-5 baddies appearing that you need to shoot. Then a small "cutscene" where you see this guy going out of a door, and you can't bloody shoot the fscker until you've seen the cutscene, and have, what, 100ms or so to click you button. FRU STRA TING!