Four-seam vs. two-seam grip for beginning pitchers

Question
I have gotten several different opinions at clinics and from coaches on how beginning pitchers (ages 9-11) should grip the ball. One viewpoint is the four-seam offers more control for little hands and a more consistent rotation. The other says placing the finger along the length of the seam offers even more control, with increased rotation and speed.

What is the best grip to start off young softball pitchers? Or, more precisely what are the ups and downs of each?

Answer
I always liked the starting a beginning pitcher using the four seams simply because it gives them a degree of comfort and control.  It also helps reinforce them using the pads of the fingers. In my opinion two seams does increase the pitching speed however it抯 only marginal and the ball tends to cross the plate flat.    Four seams provide more ball movement and I抣l take ball movement over pitch that is a couple of MPH faster but flat.