Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Unexpected Surprise!

I am so glad I tried these bottles! I didn't really think they would make a differece but they did. My 5 week old son would squirm and spit up after a feeding. When he wasn't sleeping, he would be fussing. I tried playtex and avent and assumed he would just have to outgrow his gassiness. So I was pleasantly surprised to find out Dr. Brown's worked just as they claimed to. My son eats calmly now and doesn't spit up. He seems much more comfortable and I'm very pleased!