I've read and heard a few things about these hot taps, which can either be part of your kitchen tap or just at the side of the sink, giving instant boiling hot water. Sounds ideal as we're always boiling the kettle for just one or two cups of tea and getting rid of the kettle would free up more worktop space.
Has anybody got exepierence with them. Are they good, do they last, what about efficiency etc?
If so what brands are best value/performance/durability etc.

