Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Not good if your baby doesnt have gas problems

I bought medela and ventair bottles when my baby was born (hes now 3 months). they both came recommended by our breastfeeding class's teacher. my baby doesnt really have any problems with air bubbles, gas or spit up so the ventair was just an extra hassle for me. you cant pump directly in it, or shake the bottle too hard cuz the milk can leak out of the vents, and sometimes a little bit of milk gets deposited under the vent. since its my breast milk, i hate having to let it go to waste. Not a big fan of the nipples beings so thin either. and u cant use them on any other bottles cuz then it takes the baby ages to drink from it (they're designed specially for the ventair). and it doesnt even come with lids! even the caps are not that good.the only thing i like about them are the shape. easy to feed the baby with.all in all, unless ur baby NNEDS airvent bottles, i wouldnt recommend it. im sticking to my medela bottles!