Never overload this movement. It can cause unwarranted knee pain.
Always use this exercise for volume, keeping reps over 10.
Wear you point/position your toes will have an impact on the stimulus of the quads.
During the eccentrics and concentric portions, focus on the mind-muscle connection of the quads. They are controlling the weight, not momentum or excessive bodily movements.
*Tips*
Use this movement at the beginning of your training to prime your quads, or at the end to completely exhaust them.