I've tasted red bull but I don't like it one bit. To me it tastes like liquid bubble gum.
Besides I don't really need energy drinks if I want to stay awake as I rarely drink things that have caffeine in them so one cup of coffee does the trick. Not that it's a principle or something, I just have a habit of drinking orange juice at home or beer when I'm going out.
I once couldn't sleep all night because I drank 1,5l cola during the day. Yes, 1,5l cola during +- 12 hours = staying awake for 38 hours.