|I used both the S Sandys and OS from 6.5 lbs with my DS#2 (8 lbs with DS#1), and both worked very well (wasn't sure how they'd work at those low weights, but was sick of pee leaks with disposables). I actually found that the diapers looked bulkier on my chunky #1 than on my skinny #2, strange but true.
I had planned on phasing into cloth, assuming it was going to be more work, have more leaks, etc., but it's been great from the beginning. I had already started to get some blow-out leaks with disposables, and ME diapers were the best for keeping the poop in the diaper instead of all over everything.
I also found that once we switched to cloth (it was about 2 wks with my first), my husband was more comfortable handling him, as the diaper gave baby a bit more of a solid feeling. And since cloth diapering is what my husband learned, he was very comfortable doing it (but didn't feel confident changing disposables).