Yeah my DD was always a greedy little thing... at a couple of checkups with her the doctor told me I had to 'stop feeding her so much' because she was in the 97th percentile for height and weight, and she was feeding every hour or two without fail. I tried sticking to the 4-hourly feeds she recommended, but DD just screamed and screamed and screamed, so I fed her whenever she wanted it and she's never suffered for it - the weight all fell off when she started crawling/walking, and she settled into 3/4-hourly feeds when she wasn't going through growth spurts.

I don't think there's much difference between demand breast-feeding and demand formula-feeding - all babies are different, and have different needs, so as long as bub is thriving and happy, don't take too much to heart the advice of a tin of formula or people who aren't with bub all the time!!