My daughter picked the aurora pattern herself and now actually remembers which bottle is hers at school. The sleeve pops off without a fight when it's time to wash, which beats the last bottle cover we had that clung on forever.
The sleeve slides on and off in seconds, so I can swap the Aurora pattern for a plain one when my son decides he's too cool for it. The swappable design is a smart way to refresh the bottle without buying a whole new one.
My daughter picked the Aurora pattern herself and now actually remembers to grab her bottle before school. The sleeve pops off for washing without any wrestling match, which I appreciate more than she does.