Best for what? What's best for my kid right now is a sippy cause she hasn't mastered the straw yet. But we normally have a sippy and straw cup with water everyday to work on it.
I think when we discussed this in the past, it was said that SLPs suggest a straw cup because the way they manipulate their lips and tongue is better for speech development. Since they shouldn't be walking around with it in their mouth all day anyway I don't see a difference. We use both, but a regular sippy most often.
Re: straw or sippy?