My lovely husband bought me this, because he saw South Park and thought it was hilarious and because I need to lose weight in a low-impact sort of way due to chronic pain and arthritis.

Likes:
I can see how this would tone up your arms and chest, just like it says it does if you use it daily for several minutes.
I would imagine it also burns some calories with use.
It's quite small and easy to store


Dislikes:
I have really small hands, and getting my hands around the shake weight is hard and uncomfortable.
I also have carpal tunnel, so this really isn't that good for me and my many health problems.
Maybe I'm not that coordinated, but I don't find this easy to use at all, I find it hard to make it shake without wobbling.
I feel pretty silly using it.
It's quite expensive

Overall, I don't really like this, it isn't suitable for my small hands and chronic pain, so really it's just gathering dust somewhere in my house. If you don't have all the many issues I do, I could really see it working well, if you are dedicated with usage.