Ok so you link me both the guns and it doesn't even show what the perks do... Ok then. Still it's all about where you aim anyway. Half the time I aim too high/low and have to flick up/down to headshot and if I don't I usually get shot in the face after I tickle their chest. Aim assistance might help you for a half second/ full second but if you pull the trigger before the aim assistance drags your scope it doesn't matter. The trick is know where sniper spots are on both sides of any map you play on. Honestly that's what it comes down to for me. Know the spots and pull the trigger first and if you don't hit em in the head you better get the hell outa dodge