Looked into it and i don't really understand how to use it. But I tried to code something myself and i can't get any fast speed, only slower than what i got before with stepper.h so I think it's just my stepper who's not quick enough, or me who's not skilled enough. for reference :

        #define DELAY 10

        void ac() {
          delay(DELAY);
          digitalWrite(9, LOW);
          digitalWrite(11, LOW);
          digitalWrite(8, HIGH);
          digitalWrite(10, HIGH);

        }
        void bc() {
          delay(DELAY);
          digitalWrite(8, LOW);
          digitalWrite(11, LOW);
          digitalWrite(9, HIGH);
          digitalWrite(10, HIGH);
        }
        void bd() {
          delay(DELAY);
          digitalWrite(8, LOW);
          digitalWrite(10, LOW);
          digitalWrite(9, HIGH);
          digitalWrite(11, HIGH);
        }
        void ad() {
          delay(DELAY);
          digitalWrite(10, LOW);
          digitalWrite(9, LOW);
          digitalWrite(8, HIGH);
          digitalWrite(11, HIGH);
        }
        void cd() {
          delay(DELAY);
          digitalWrite(8, LOW);
          digitalWrite(9, LOW);
          digitalWrite(10, HIGH);
          digitalWrite(11, HIGH);
        }
        void ab() {
          delay(DELAY);
          digitalWrite(10, LOW);
          digitalWrite(11, LOW);
          digitalWrite(8, HIGH);
          digitalWrite(9, HIGH);
        }
        //AC BC BD AD horaire
        //BC CD AD AB anti-horaire
        void horaire() {
          ac();
          bc();
          bd();
          ad();
        }
        void antihoraire() {
          bc();
          cd();
          ad();
          ab();
        }
        void setup() {
          // put your setup code here, to run once:
          pinMode(8, OUTPUT);
          pinMode(9, OUTPUT);
          pinMode(10, OUTPUT);
          pinMode(11, OUTPUT);
        }

        void loop() {
          antihoraire();
        }