I had a jumperoo for each of my daughter's when they were young. For some reason I had the two most crabbiest children when they were babies. It seemed that nothing would calm them down, until we got smart and invested in a jumperoo. I did not know that this would make them so happy. They would wear themselves out so much that I found them snoozing in it a few times!
We bought the Rainforest jumperoo for our youngest Emma because I think she was at the age where she wanted activities to do but she was still too little to play with toys. I could not believe how much fun she actually had with it! We would laugh our butts off at her because she would jump nonstop. It was totally hilarious. She always wore herself out and would fall asleep.
Assembly was super easy, and it only took about 10 minutes. I know that they are kind of expensive, but I totally think that they are worth it. This is a must have for babies! It strengthens their legs so that they can start walking. I highly recommend the Rainforest Jumperoo by Fisher Price. Your baby will thank you for it!