the confidry are pretty thick, but they are a medium-sap diaper, and so they don't swell as much as a high-sap diaper does. They start out thicker than some, but may end up not as thick as some when fully wet. But the thing is, they still wick really well. Adding more sap may raise their capacity, but slows wicking, and that will tend to lead to a leak unless you can keep your wetting slow. So I'd call the confidry one of the highest "safe capacity" diapers available. They're my first pick on those evenings when I've drank a lot and expect a lot of wetting overnight.
The waddler overnight and the bambino bellisimo may be able to get larger when fully saturated, but getting there without a leak takes some care. (I have yet to fully use a waddler overnight, they have a deceptively amazing capacity)