I think we were an exception as I used them exclusively until Evie was about 7 months old and got on really well with them, both during the day and overnight. In saying that once she reached 7 months the next size up were huge on her so I started looking at other nappies (and havent stopped
)
I think as well it depends on the wrap you use - the Bambino Mio wraps I got were pretty bad, I bought some Nature Babies and Tots Bots and they were fab. I suppose it also depends on whether your child is a moderate or heavy wetter - Evie was quite heavy so I added a booster to ours, as I say, no problems.
I wouldnt go buying a full set - you can pick up prefolds really really cheaply 2nd hand.
Sadie xx