Are you both buying extra-duty (black label) balls?
Originally Posted by Ramon
... You can tell right away that they have a different colored felt, which is supposed to be better under night lights. I thought they were better than the Championship balls in terms of consistency and durability.
I do like the Pro Penn Marathon, which I think is their top-of-the-line ball. If you can past the fact that the regular felt fuzzes up early in the first set and wears down after that, it's a great all-around ball, but the Wilson US Opens last longer.
The ATP ball and the Marathon ball are both
considered to be Penn's high-end professional balls. The Marathon ball was developed for durability/longevity for teaching pros. The ATP ball OTOH was developed for ATP pro tournament play where longevity is not a primary concern (since 6 new balls are put into play every 9 games). The ATP ball is indeed Penn's brightest ball and its precise, consistent bounce and quality control is superior to that of the Penn Championship balls.
The Penn Champs seem to be a bit softer than Penn's pro balls and tend to lose pressure quicker.