It did really well! The fit was great, nice and snug but not tight, and it covered the WNNN easily. Ds slept well all night and we had no leaks or wicking. He did look a bit funny, mind, huge bum
The only downside was that the fleece bobbled a lot after just one wash. I know fleece bobbles, but this REALLY bobbled, so that was a bit disappointing. Still, it's only for night-time and it works brilliantly, so not a problem really.