Lightly Carbonated. Serve Chilled. Red Bull claims that it "Vitalizes body and mind". The back of the can states, "Improves performance, especially during times of increased stress or strain. Increases concentration and improves reaction speed. Stimulates the metabolism". The can looks pretty much like the "classic" red bull, with a lighter blue, to let people know that you're afraid of sugar. It contains phenylalanine, so the small percentage of people with a certain condition who are sensitive to this chemical, should avoid red bull sugar free.
The initial taste is much better than regular red bull, but the aftertaste lingers for some time, like an aerosol hair spray directly in the mouth. The 10 calories is good, but they make up for it with a lot of sodium, so it's not thirst quenching at all. I think it's a reasonably tasty beverage. I'm hard-pressed to give any $2 8.3oz soda a unsullied review. My complaint with Red Bull from day 1 has been quantity to cost. It has a reasonable energy kick, and is a good choice if you have a bladder the size of a walnut.
I think that it's good when companies become more health conscious. But honestly in this day and age, does it really matter? If you want to make your mark as a 'healthy' energy drink, it would have to be no sugar, no carbs, no sodium, no msg, low calorie, with extra tree bark and high fiber dirt. So does a little bit of sugar really matter? I thought we were all carb conscious now anyway. Low sugar drinks are so last year. Besides, most energy drinks average about 30g of sugar per serving. That's one ounce. Plus it's less sugar than you'd find in a Sprite.
So just because you can succeed in making an energy drink with no sugar doesn't mean you should because obviously to make it that way you have to add perfume to it. And I don't mean aromas or flavors. I mean perfume, like when you walk into a department store and some woman sprays you with some new fragrance and swears that now your man will be all over you, and she just so happened to catch you when you were yawning and now it's all in your mouth. What the lady at the counter doesn't tell you is that perfume is made from secretions from a variety of animals including, cat, deer, beaver, and some type of scab-like substance that forms on the inner lining of sperm whale intestines which are eventually 'excreted', meaning crapped out. This is called ambergris, and this is not made up. That kind of perfume taste, along with a little fruit flavor and some syrup.
I don't think there was much of an energy boost. I didn't fall asleep, but I didn't chug this down because I wanted to feel like I got my money's worth of soda. Less than two minutes worth of soda does not equal $2 of soda.