Any motor can haul 300kg up a hill. It's just a question of how steep the hill is and how fast you go. The 100w motor might manage 1% at 8 mph, Bafang HD 12% and Heinzman 25%. It's simple physics: 100w vs 1560w vs 3000w. If they all go at the same speed, the max hill steepness they can go up is...