This exercise is not for absolute beginners. The balancing aspect of this movement makes it more challenging than doing it the classic way - on a flat bench. Thus, if you're a beginner you are better off doing this same movement on a stationary flat bench.
For those who are more experienced this exercise is great to add to an already existing chest workout routine to give some variety to a stale chest workout program. It's fun to do and in addition to working your chest it will impact your core as well. Thus, all-around, the benfits of this exercise are significant.
It's worth mentioning that it's important to set up properly on the ball with this exercise. If your neck doesn't feel completely comfortable that means you didn't set up properly. Find that sweet spot on the ball where your head is not sticking out too far past the ball and where your neck feel just right.