Kangovou Stainless Steel Sippy Cup (Peaches and Cream)

It seems really great - stainless steel inner, double-layered for insulation, snap-on top that can convert from straw to open spout to open cup for toddlers learning to drink. But in reality, the tabs to snap the top on broke with one fall - on two cups. I liked it so much in theory that I was willing to give it another shot, and the same thing happened again. And my 16 month old figured out almost instantly how to get the top off. I much prefer the Thermos Foogo.