Initially I disliked the taste; then I tried it for the 'energy' since I don't drink coffee (and like Guarana, being from Brazil) and just kept drinking it..
These days I drink one can per day around the time I arrive at the office, but I'll probably either reduce considerably or just stop drinking it - from a simple short experiment it seems to affect my sleep quality (didnt drink redbull since last Friday and my sleep quality improved/felt more rested with same amount of sleep time... Then had one yesterday and today I feel sleepy and jumpy again).