I want to try this. If you're happy with yours can you link to it? (everything I'm seeing is either under $10 or over $20 so I'm not sure which way to go)
As for being happy with it - yeah pretty much. It's not like it's mind blowing or anything and I've not tried any others to compare it to, so take that for what it's worth, but it works.
I keep mine next to my desk and use it when I'm bored or need a moment to think. I tried following the recommend pattern of use in the instructions but didn't stick to it for very long. Now I just use it when the fancy strikes me.