From what I remember in Cochlears description of the Nucleas 5 they tested it for up to 30 minutes in water! In the Freedoms brochure that came with my daughters freedom it showed a girl swimming with dolphins and a boy running through the sprinkler, that was one of their marketing adds!
My daughter has always gone swimming with her CI on whether it was her old Freedom or her new Nucleas 5! She wears it in the bath, the pool (we go twice a week), water parks, you name it and we have never had a problem with either processor! And yes it has gone under with her MANY times lol. Thats what warranty is for:P Maybe once the warranty is up I won't feel as comfortable doing it, lol, but hopefully by then there will be a new model out and we'll have a new warranty, lol.