You cant use purely statistics without factoring in player skill. The slower fire allows better accuracy. How much dps increase this will cause is different per player (one could argue that a player should be skilled enough to make all-crits in both situations, a bit unrealistic id say). You get more dmg per magazine, you get better accuracy, you dont need to reload as often, becomes more effective at a longer range. Those are all factors that need to be counted, not just flat dps. And then there is ofcourse preference. Oh, and on average, more than half my scoped shots are crits, something i couldnt do as easily with a higher rof.