It depends slightly on the height of the box of course.
For some reason, boxes that are above parallell have become very popular at certain powerlifting clubs.

With a lower box, there is a bigger ROM of course.
Then again, partial reps training can always be a good supplement, but as Magoo and several others are implying, ass to calves squats gets the best ROM.
The foot placing is also of importance. A shoulder width, or slightly more narrow stance, will target the quads very nicely. Opening up the stance, will involve the hip, the ass, the back et al.
JMO.