My wife and I are both VI and play VI Tennis once or twice a week. We tried these as an alternative to the current balls made in Japan. In comparison Buzz Balls feel better made and more durable though we haven’t had them long enough yet to determine how long lasting they are. But we have played 4-5 hours of tennis so far with no loss of bounce as yet.
They do move a little bit quicker than the current ball as they do feel slightly heavier, and have a stronger bounce. They also bounce straight. Generally they don’t feel too different to play with. You just don’t need to hit them quite as hard. Would recommend them. Plus it is a UK company employing VI people and have a good eco-friendly ethos. All good reasons to support them.