I only have the TL biggsies because I prefer a longer pad. I still have some Libra goodnights and the TL is 31cms long and the Libra is only 30. I would imagine that the middsie would be similar to a regular pad. You could definitely use a post partum pad for overnight use as well - most commercial pads are sold as nighttime/maternity use. And you're right, the quality is excellent. Mine have PUL, but if you didn't have an overly heavy flow and you changed them often leaking shouldn't be a problem