Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Pump is great; bottles and sealing stink.

This is a great pump. I haven't had any issues with it. I pump constantly as my son is very finicky as to when he wants a bottle or a breast in his mouth. Easy to use and clean. The carrying case is great for when I go back to work and it can also be used as a carrying bag for keeping milk/formula cold when you go out. While I love the pump I am not happy with the Avent Bottles. They can leak easily if you over or under tighten the bottle. Let me tell you at three in the morning you dont' want to worry about that stuff. You want to get a nipple on and feed. I recommend the pump but not their bottles. Sometimes if I put down the pump on the bed and it tips a bit I get spillage from where the pump connects to the bottle.