I used small bubblebubs and NB Magicalls on my little girl from about 4 weeks, but she was only 2.6kg at birth. I think she was about 3.5kg at 4 weeks. We havn't had any leaks as yet. Although i do need to boost the magicalls.
I think Berry Plush have a small AIO??? Can't quite remember, think i saw them at the baby expo in melb.....
I only had 2 bubblebubs and 3 magicalls. So was using terry flats and covers most of the time. And had AIO's for special occasions!