Thanks, Amber! I haven't actually made AIOs yet... Just PUL covers. My solid PUL covers haven't wicked unless the diaper underneath was so completely saturated that it couldn't possibly hold anymore (that's very rare that it happens, of course!!). In fact, earlier this week, DH took DS with him on an errands run. I put him in a regular sized prefold with a preemie size prefold folded up in the wet zone, then put a 1 layer 1mil PUL cover (bound with FOE) on top of that. They were only gone a couple hours, but DS drank an entire sippy cup of water while gone - he just sucked it down! So of course when he got home, both prefolds were completely soaked. There wasn't a dry spot or even a slightly damp spot anywhere. Yet, his clothes were completely dry! The cover held it in perfectly.
I've had wicking at the legs on my cotton print outer cover (PUL on inside, cotton print on outside, bound with FOE), but didn't used to get that. Not sure what changed, since this is OSDS PUL and never was treated with DWR! It may be just that DS is a heavier wetter now than he was when I first made that. He has recently increased the amount he pees at one time (I think he's holding it and then flooding).
I also don't usually get wicking with a cotton print outer Luke's Drawers AI2 (serged), unless the soaker gets so full that it leaks onto the tabs (side-snap diaper). This is where I think side-snap isn't such a good idea.

Anyway, it has a tri-fold soaker in it - just 2 layers of velour. I tried making a hemp/velour soaker to replace it, but I accidentally made it a bit wider. Guess what? It wicks EVERY TIME when I use that soaker. I guess because of the width. So that can make a difference too.
