I liked Flora Power at 30c3, but still prefer the Californian Guayaki unsweetened mate (in a snapple-type bottle).

http://guayaki.com/product/127/Unsweetened-Mate-(Case-of-12)...

There was a period it was 4 for $5 at Whole Foods.

Flora Power was surprisingly great, and indeed a little less sugary. Tried it at 30c3 for the first time too.

1337Mate used to taste like Flora Power, only with more caffeine, but now it tastes like marshmallows :(

I drink my coffee black. but sugar is great, someone has to say it.