We use the natural for DS2 and they work great and are super easy to clean. We used Born Free with DS1 and they were amazing for his reflux and easy to clean.
We tried both. DD latched onto the classic immediately and loved it. She seemed to struggle with her latch on the natural bottle and it took her double the amount of time to drink the bottle than with any other type of bottle. We use the Avent classics in addition to several other bottles, but I love the Avents the best because there are so few parts and like I said, DD loves them and her latch is great on them.
Re: Avent Classic vs Avent Natural Bottles
BFP #2: 11-7-14, CP (BFN: 11-13-14)
BFP #3: 3/24/15 EDD: 12/5/15