I bought a dz and I noticed that I have a had 2 balls in there that seemed to wear a little worse then the others. Seemed odd, but it could have been an end of line issue or something. It was odd though. I had one ball look almost new after 36 holes and another look heavily used after 12 holes. Same course, same clubs.
I went this afternoon and played 9 with a Q-Star Tour. Hit all the clubs as well as an oak tree. The ball still looks like it just came out of the box.
As you suggest, there may be some inter-batch variability issues on their line.
BTW, the ball performed very well. I specially like the way it likes to get into the air.