Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Love these bottles

I really do love these bottles. My son was exclusively breastfed until 3 months, and these were the only bottles he would take. We tried Avent, Playtex Nurser, and a few other kinds. This was the only type of nipple that he liked.I've seen complaints of nipple collapse. The reason for the nipple collapse is if you warm the bottle with the nipple on. It says right on the bottle "Remove nipple to warm." Also, with the vent at the bottom, I haven't had one problem with it leaking. Just make sure it's in good. If you are breastfeeding and are starting bottles and choose this one, I would recommend stage 2 nipples. That's what I use for my son, it has a faster flow.The only problem that I have had with this bottle is because of the curved neck, my son can't figure out how to give himself the bottle. But at least he's taking a bottle! :)I love the VentAire and highly recommend them.