The free flow sort with the spout that folds down.
I can't put the lid on without squirting myself in the face with the contents.
I can't take the lid back off without a huge amount of effort.
They are not non drip so DD takes great delight in watering the sofa/floor/cat.
They only come in 3 different colours so every child has the same beaker as your own.
Can someone tell me it's a myth about the ones that are not free flow being bad for their teeth development (or something like that)?