I shoot 4 4inch flex fletch with a twist. I dont think it make a huge differance but when i shot 3 vains me and the old man were messing around shooting 100 yards and i noticed a slight wobble in my arrow flight. I told the old man i needed to check my arrows through some paper. He gave one of his arrows and told me to shoot that (4 vain) therer was absolutly no wobble at all. Ive shot a 4 vain ever since.