S.N.
The variable flow nipples are sort of pain to deal with because you have to look carefully at the nipple each time it goes in your babies mouth and line it up accordingly. My little boy used the Flow 2 nipples until well after he turned 1 years old and I only bought the Flow 3 nipples because I felt terrible that he was still using the Flow 2's. Did you know that Babies R Us carries the Born Free brand now? Good luck. S.