I honestly think ppl have just forgotten how to be in the powerband. I'm a novice rider and really try to be unbias when I ride the f and the sx but I just cant turn that four stroke. I'm the kind of two stroke rider that cuts off lines and exits early so whenever I ride the f I just feel like I cant turn the dam thing. Then the engine brake thing really f's me up no pun intended. Overall I'm two to three seconds faster on the 150 than the F with that said if the day ever comes that two strokes arent a part of motocross is the day I quit motocross!