Yes to what everyone else has said. I use one and like it.
Money is the not the issue, they are cheap, but from the first time I saw one, with a coach demonstrating overhand throw, overhand wrist flicks, and how to point your palm or whatever to second, I said no way. One of my current pitchers really dislikes it. She uses a ball on the stick at low resistance, high reps, and they can use a grip that is exactly how they would hold it.
We bought it originally because of it showing the spin and DD hated it at first. Prior to getting it, they were complaining about her always throwing hard curve balls. We got it about the same time we started Austin's throwing program and bust it out occasionally to use while warming up.You don't have to do wrist flicks with it. That's on the coach, not the devise.
My older DD didn't like it, but mostly because it showed he spin was off.