I really like it. It has vibrant colors, a nice material that doesn't slip from the child's hands, and a decent size so you don't have to constantly refill it with water or juice.
Now, it really doesn't fall easily. If the child makes a careless movement, it doesn't tip over like a conventional cup. However, if they do it with enough force, it will fall.

Completely impractical, it sticks with a very strong suction cup, not even an adult can remove it. A child has no way to use it. Money wasted!