These balls are light, fast and super-bouncy. For harder hitters they are very difficult to control on a fast court surface such as macadam/tarmac. As the felt wears away rapidly, they become even faster and even more high bouncing.
In the end, I discarded these after an hour's hitting. Both I and my hitting partner agreed that they were lighter and less stable in the air than better quality balls, and the bounce became increasingly erratic.
Not recommended for advanced players but the high bounce might combine better with a slower/beginning level play style. As an intermediate player, I bought them out of curiosity, knowing they were aimed at beginners, and I regretted it!