When I used to have small critters, such as dwarf hamsters and teddy bear hamsters, I had several of these for them. In fact, at one time when I had half a dozen different hamsters, I had half a dozen of these balls - one for each! Nothing was more amazing and silly to see five or six of these going at the same time.

Great selection of colors available and its a great product to keep hamsters active and get some physical action going. My only complaint is that depending on the model of how it snaps together, it can be difficult to clean the inside of the ball where the hamster may go potty.

Pros: great for exercise for small critters

Cons: can be difficult to clean the inside

I have the 5inch hamster ball and it works great for my dwarf hamster. She just loves running in it. It is perfect for her and easy to manuver.
I had a bigger one and noticed that she had trouble getting started, but with this one she goes cruising through the house.
The only problem i found with this ball though was getting the lid off.

Pros: Great for my dwarf hamster

Cons: very hard to get the lid off

great form of exersize and fun for critter and kids!

Pros: lets animal exersize

Cons: none

When I was young, I had a hamster. We bought one of these exercise balls for him. He loved it and it was rather entertaining for us, too. You could put him in it and just let him buzz around the house and not worry about him getting lost. Every hamster should have one of these.

Pros: gets them out of the cage

Cons: none

My hamsters had a blast with this and enjoyed exploring the house.

Pros: fun for hamsters, cats, and dogs.

Cons: nothing