Instruct: Classify Amazon reviews into positive or negative sentiment
Query: AWFUL BOTTLES

I bought these after my Avent bottles started to leak. At first they were okay, but then my son had trouble feeding from them. The flow was too slow and when I made the whole bigger it was too fast. Also you have to check every new nipple to make sure there is a hole at all! IF you tighten the bottom too much, the baby can't get any milk. Whenever I used these, I kept having to stop my son from eating to make sure he was not just sucking air. Also the nipple collapes ALL THE TIME. Try the Playtex Premium Nurser. It works much better.