Better than what you can get in the store, I can tell you that. But they're just not made to take more than two hours(two hours of saline drip, granted) so they have a limit they're designed for. Think of it like, why do we need more absorbency if it's not going to be worn that long?
Incontinent people who live independently have different needs, so we have m4s.>>1272679
Nah, most good diapers have them. It's just too useful a feature.