"I purchased some of these cars on a trial basis for my toy store. Kids love them (I even had one of them shoplifted!) They are a really neat idea, but the only problem I had was the balloons were difficult to inflate and the cars did not go very far and they tended to flip over. Kids didn't seem to mind. I tried adding larger balloons which helped the cars go farther distance, but the cars still had difficulty staying on the surface without flipping over. The screeching sound was pretty cool, though."