Our 1 year old is a pretty heavy wetter, and the Smartipants lasted very well against the tidal wave of wee that he produces. It was only when we worked out how long the nappy had been on for that we were really impressed with its absorbency.
We soak them over night and then put them through a wash, the nappies are usually day by the end of the day, it out on the line within a couple of hours maximum.
Overall, very impressed with the nappy. Will be getting some liners to deal with solids though - yuk!