Comments about Tretorn Micro-X Yellow Bag of 72:

Have read some posts here that are bit over the top. First off let me qualify my opinions by saying I've practiced with and owned ball machines all my life for over 30 years. Make no mistake, the reason you should buy these balls is for practice only! They do not feel just like pressured balls because the pressureless core is harder than the pressured core thus creating a hard feel compared to the soft feel of pressurized balls. This does not change over time as one poster suggested,in fact they become harder as the felt wears off over time (I am going on three years with my original 180 ball order). However, that is the only negative I have found with these balls. The bounce remains consistent over time and against other balls in the group. This, to me, is the most important characteristic because if you use them for ball machine practice they give you the most consistent solid bounce every time the machine releases a ball. Anyone with a ball machine knows that if you use various aged pressurized balls the bounce is directly impacted by the life of the ball, and nothing is so frustrating as setting up a ground stroke drill and 1/2 the balls bounce differently than you intended thereby rendering the drill almost useless. If you use them for practice and drilling purposes only - they are absolutely worth the extra price (I purchased cheaper non-micro technology the first time I bought a ball machine and they were as hard as rocks, never lost their bounce, but did not resemble "live" balls at all). It is my overall opinion that the micro technology provides the closest bounce feel to pressurized balls, but to say the bounce and feel just like pressurized balls is just not true - only if you are an in-experienced user and just can't tell the difference.

Comments about Tretorn Micro-X Yellow Bag of 72:

Used for practice, good feel and finally I can say goodbye to my old dead practice balls.

A little hard at beginning but they get better with use.

They provide good feel and bounce. These are for practicing so I don't recommend them for regular play. They are playable but a bit harder than regular balls.

Comments about Tretorn Micro-X Yellow Bag of 72:

Have been using in a ball machine for practice. Am looking forward to not having to replace practice balls every few weeks.

Comments about Tretorn Micro-X Yellow Bag of 72:

I originally bought 144 balls for use with a ball machine hoping for consistent bounce and durability over time, but based on reviews on other websites hoped these act and feel like a normal pressurized tennis ball: 7 weeks of use and totally satisfied. They play and hit like a pressurized ball and my coach who played on the pro circuit said they feel like a real ball (only difference he could detect was the sound when hit is different). They seemed extra fuzzy at first (lots of fuzz coming off in the machine) but after 7 weeks they seem just right. Thought I'd just use them in the ball machine, but we use them for match play now too and my coach approves. Holding up well and I hope to get a years use out of them at least. (Read one review of guy using the same balls for 8 years and he swears they bounce like new pressurized ball and still have great felt). Time will tell but everyone who comes to hit with them is impressed/ can't believe they are hitting a pressureless ball. Some reviewer complained that the ball felt harder to him and thought it made his elbow hurt, but I haven't had that problem at all.