I used these bottles with my first child over 3 years ago and am using them once again with my second baby. I liked them because I had my first baby when the dangers of plastics containing BPA was all over the news and I knew that these would be safe. I exclusively pumped for both my babies and they fit perfectly with my Medela breast pump. I found that for the price, their durability, and the ability to use most standard nipples with them, they were the best brand of bottles I had purchased.