I had a stash of half FBs with Isis and I hated them, they were so leaky, and forget about using hem overnight, regardless of how much I stuffed them!
They've changed since then, and come in OS and I hear people rave about them, especially for nbs since the crotch isn't overly wide. I have one what is labeled "one size" fb and put it on my 8 pounder last night. How is this one size? There's no rise adjustment!! She looked like she belonged on a golf course in FL sporting the latest hearing aid, and there were still gaping holes around her legs!
I just don't understand how a diaper w/o a rise adjustment can be consider one size. And I still don't understand why there's so much love for FBs. But that's just me. To each their own. :)