You wouldn't believe the number of world travellers and backpackers who are using this, including our own daughters.
One in Belize, who is obtaining any water and not worrying about it and the other in London, who uses it to remove the hard metallic taste!
Sports people, such as endurance riders, cavers (especially) paddlers, etc etc are now able to draw water from normally dubious sources and know it will be okay, without having to wait for Iodine etc to take effect. Saving weight, bulk and energy.
Water. The new gold? Such a simple commodity, surrounded by it and yet worried about drinking it. Makes you think doesn't it?