I'm also curious when you switched nipple flow. We use playtex ventaire and they have slow or fast flow. Alexis just finished her bottle with the fast flow so quickly that im worried she may get a tummy ache now..but had to use it to test the new formula (post below)
Spontaneous ID Twin Girls - born 38w 2d
Re: Nipple Flow
They have medium flow ventaire nipples at walmart but they seem to have a hard time keeping them in stock.
My guys moved up pretty fast. We've been on the fast flows since about 5 months.