Chris wrote a review of Nuun Mixed Fruit Nuun Tube - 4 Pack on March 29, 2012
I bought the mixed flavor pack because some flavors aren't as good as others. However, to my surprise, they were all terrible. The recommended dosage tastes extremely watered down, but adding more does not really improve the disgusting fizzy taste.
It may be full of all sorts of essential vitamins and electrolytes, but I actually dreaded drinking the water. This is completely counter productive to the purpose.
It wasn't just me. My entire backpacking group of 5 agreed.