Thelondonpaper, the paper you always ask for when someone thrusts a London Lite at you, thought Firefly Waters were rather fine:

"Wean yourself off" the "sugar-rushes masquerading as fruit juices" [smoothies], and switch to "Firefly's new anti-oxidant infused waters", with "a third of the calories of fruit juice because Firefly uses Agave Nectar, a natural low-GI sweetener".

Thank you London paper (sorry, we're not allowed to put the article up here - News International are rather strict about it.  Much as we love them...)