We use our bG at night, stuffed with two JoeyBunz. If he wakes up to eat, we have to change him or he'll leak by the morning, but that's more because he pees like crazy than because of the inserts.
We don't use the CottonBabies insert at all at night, as it doesn't hold anywhere near as much as the JoeyBunz. I've read that microfiber (as in the CB inserts) is too drying to go directly against the baby's skin, and can cause rashes for many babies. Plus the microsuede liner is what keeps the baby feeling dry, so I like to put all the absorbent material under the microsuede, in the pocket.