My son, who is about to turn 13, used it last year and it was a great bat. It is a -9 and end-loaded so your mechanics have to be correct. The ball shoots off the bat. My son was only 5' and 100 pounds but won the league home run contest with that bat and everyone of them were line drives that were still ascending when they cleared the fence.
Their one year warranty is great. By the end of the season, the inner wall had worked loose. I sent the bat in and had it back in less than two weeks in perfect condition.
I am looking at getting him the Pyrotech XT, -5, for his transition to high school. From what little I have heard, it too, performs well.