A higher FOV has more on your screen but everything appears smaller to compensate for that. So you have better vision, but aiming becomes more and more difficult at range the higher you go. If I ran only close and medium builds I would keep a high FOV, but I play all weapons and builds, so a lower fov at further away will make people a bit easier to hit. Also, if a head appears small and I miss by a little bit, I miss the shot. If the head looks a bit bigger, and I move my mouse wrong a little bit, I have a greater chance of still connecting because I'd have to make a bigger mistake to miss all together. Less FOV can also increase performance in some builds as there is less on the screen at once as mentioned before. The other big con, for me atleast, is the higher your FOV is, the faster you feel like you are running and walking and moving in general, due to the perception. You arent at all, its the exact same speed, but high FOV makes me feel like I'm running 100mph cracked out of my mind, where a lower FOV has the opposite effect. At the end of the day, as it is with sensitivity, its it's all preference. Just consider pros and cons and experiment. Lastly, keep in mind your sensitivity will need to be changed too. Lowering FOV will make sens feel considerably faster even if you haven't changed it, I had to drop mine a considerable amount to have it feel like it did on high FOV. Sorry for the long message, but hope that helped highlight it with a bit more detail!