This is really, really good - it pulls all the condensation and gunk out in one quick easy pass.
Only one, admittedly small, draw back - the weight on the end of the line seems to easily get hampered when you are setting it up - it rarely drops straight out of the bell first time. I suspect that this either because the line could do with being 300 - 600 mm longer, or possibly be made of a slicker fabric or both.
But in terms of swabbing out - it's in a class of its own.