Originally Posted by SystemicAnomaly
Perhaps you got a can of balls that had a cosmetic flaw on one of the balls (instead of a substandard bounce). I see that happen every once in a while -- perhaps 5-10% of the time.
Usually, with the substandard ball, the bounce height is about 80-90% or so of the other two balls. Perhaps you got one where the lower bouncing ball was 90+% of the other 2 balls so you may not have noticed it. I have seen hundreds of cans of Penn Champs where one of the balls had a substandard bounce.
One night while playing doubles, we lost one of the new USO xd balls after 40 minutes of play. One of the guys decided to open a new can of Penn Champ balls. At that point, the 2 older Wilson balls had the same bounce height as 2 of the newer Penn balls. So we decided to continue play with the 2 USO balls and the 2 Penn balls (that had the same bounce height). After a couple more hours of play, it was apparent that the bounce height of the 2 Penn balls was noticeably lower than the 2 older Wilson USO balls.
The Head ATP ball should be identical to the Penn ATP ball -- they re the same ball with a different label. The Penn name is used for balls used in the US. The Head name is used for most other countries.
The Penn champs even look cheap. The glue is always slathered on like it was toothpaste. I seriously don't know how anyone can use those for an actual match when there are other champ balls that are so much better.