I'm trying to phase out my DS's morning and night bottle. I bought some non spill munchkin cups with the straws and they are rubbish he can't suck liquid out of the straw. Me and my partner can't either! He's no issue with not getting a bottle in the morning so I know he's ready to stop at least this one. So my question is what's the best cups to use is it ok to give non spill ones for milk only because of the smell if he shakes it onto the carpet which he likes to do with his juice cup!