I thought I would throw this out to the group. I was curious about everyone's opinion with regards to the number of holes/rounds do you play with one ball before switching it for a new one; I'm going with the assumption that the ball switch is not necessitated by losing a ball.
For me, I generally play the same ball until it shows signs of cover damage. In my early days of playing golf, I would have golf balls that would lose their shape which I would switch immediately and that does not seem to occur much with solid core balls.