I was a bit skeptical about this cat hammock/scratcher, but once I put it together (real quick & easy) my cat went right to it. I have a good sized cat, and she kind of hangs over the sides, but she still seems to like it.
I did sprinkle a little catnip so she'd be drawn to it. I have noticed her scratching the posts, so this seems do what it was meant to do...she doesn't play with the ball however...she totally ignores it.