Bambini Mio Swim Nappy
I recently purchased one of these swim nappies for my daughter and was fairly disappointed.
It comes a few different size groups based on weight so i bought the one in my daughters weight range but the fit was terrible. It was hard to get over her legs and didn't quite go high enough (so i struggled to get it to cover her bottom). The front was very baggy but the back was very small - yes, i had it on the right way (had to triple check) but it just was the oddest fit and looked very uncomftable.
Parhaps it depends on teh size/shape of your child for us it was just too akward and ill-fitting.
Not a fan.