Hi,
The point is to have the M22ti's at a height that creates the best illusion and a superior soundstage in your particular room. This will be dictated as much by the reflective characteristics of your room and the specific placement of your speakers within it (as well as your listening seat) as by the height of the speaker stands.
In my listening comparisons of the M22ti's on 16-inch and 24-inch stands, there were no significant advantages to either height, nor were there any degrading effects on the soundstage depth and imaging specificity of lowering or raising the speakers. All this applied to my rectangular living room of average dimensions. The results may be quite different for a different room and setup. Don't ever underestimate the huge contribution of the room, locations of the listening area, and the placement of the speakers relative to adjacent boundaries of all sorts.
Regards,
