once you get out to 24 inches or so,, the power stroke is pretty nice, and you can get a hard shooting bow at that draw,, ( for elk)
the shorter bows dont seem as effecient when you get down to say 20 inches,,
they will shoot hard enough,, but you might have to go up in weight at 20 inches to get the cast for elk,, the 24 inche draw bow,, will shoot close to a full draw bow,,