Rikkis are good, but the xsmall is miniscule. We only used them for a month with our 8lb 8oz fatboy. The small are a bit baggy, but they work and they really last. We didn't use any of the airflow for a couple of months. My favourite newborn wraps for terries are the imse vimse newborn size. Soft, very containing and really well fitting.
I've used Flips with my son since birth (well, once he'd passed the meconium-- some things are just best thrown away) He was 8lb. 1 oz, but long, not a chubster. I used them with the medium-small indian prefolds when he was tiny and use either those or the organic inserts now. I can't say that we've never had poo leak, but we haven't had any straight up breaches of containment.
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