I have used Gamma, Tretorn and Penn pressureless balls and these are the best of the bunch - by a mile. Pressureless balls are firmer than regular balls on off-center and frame shots, but these are not at all objectionable to me and my kids. I have used Penn pressureless balls for instruction, ball machines, and in practice games, including at high altitude. They work great for all purposes. In fact, Penn has perfected pressureless balls to a level where they should price and market them as the primary ball for recreational (non-tournament) play. It pains me to see occassional players hit pressureized balls for an hour, putting very litte wear on the balls, playing them again in a deader form in the future, and ultimately discarding them when pressureless balls would still be perfectly playable. Such a waste of money, resources, and practice time. The fuzz on the Penn pressureless balls (and the other brands) holds up very well. My one gripe is that the lid on the Penn 48-ball bucket is a terrible design. Granted most people will put them in a hopper, but why go to the manufacturing expense of making a bucket and then not put a lid on it that: 1) opens without a crowbar; 2) stays open when you are using it; and, 3) secures down when you close it. So easy to improve, it seems like basic laziness on the part of the design team. In comparing Penn pressureless with Gamma and Tretorn, my experience is that Gamma balls bounce like they are "out-of-round" and get worse the longer they are stored on top of each other - great for improving your reflexes, but wierd to play (I ended up throwing them away while the fuzz was still good) - and Tretorns are like hitting bricks whether you hit on the sweet spot or off.
