I have 2 children of my own but we have had many children pass through our home. I am an in-home daycare provider so I know a lot about what works with kiddos and what does not. This is a product that does! These cups do not need an insert. When my son was young, you had to buy the cups that had valves in the top. They worked well and they also didn't spill but you had to keep track of the stopper. Not to mention if you didn't soak them or clean them properly, they could mildew. Eventually over time, the cup would still be very usable but you might only have one stopper or valve remaining. When my daughter was born, six and a half years later, I wanted a cup that was still spill proof and sturdy but didn't want to have to buy the valves all the time. I found the answer in this cup! Not only does it have several different designs to choose from, you just fill and go! That is it. You can throw them in the dishwasher and out they come, nice and clean and ready to use again. I used this brand all the way through toddler hood and into the preschool years with my daughter and now I still buy them for use for my daycare kiddo. I don't have to worry about stoppers or leaks of any kind. I just fill them up, screw on the lid and off we go to the next thing!