I would recommend the Thirsties duo line (I just started a poll about them fitting newborns
) They generally fit newborns and up to about the start of the Medium size. With DS we used the size ones and loved them.
Other than that, as people are mentioning, softbums do seem to work from newborn on. We are all about the AI2 system and I am looking forward to trying the one that SB puts out for the next child.
I would like to mention that using softbums AI2 as designed on a newborn will probably not be very cost effective. Since newborns poo so much, you would rarely be able to reuse the cover when used as designed. SB are on the expensive side so personally I don't think that is a good idea. If I were going with a full stash of SB I would consider how much I wanted for the 6m+ phase and get that (and use with newborn of course). Then I would, personally, get newborn and/or infant prefolds (or fitteds) to snappi/bongo on under the softbum covers so we could actually reuse the covers some. Then supplement the newborn stash with thirties duo (or other nb diapers) if I felt it was needed. (to have up to 30-36 changes)
We didn't really use an AI2 system for the small size on DS so it's hard to remember but I don't *think* the AI2 system would work great until say 6months, that is about when we transitioned to mostly using an AI2 system. So having the softbums with say the thirties duo and some prefolds could be a great stash that, if well planned, could almost last through until the softbum stopped fitting without spending extra cash on softbums.
If looking at the pocket style softbums, then this doesn't help. LOL