These are great
I've taken to using these all the time now, not just in the gym where I told to. They are pretty big so make sure you have a large chalk bag. It's gotten to the point where I use it to start, then when it gets smaller I pass it down to my wife and her smaller chalk bag, then it ends up with the kids. It works just as well as any other chalk and but doesn't cover the rocks and your clothes with marks.