Yes, but they are deficient in many aspects without realizing it. For example, Alzheimers is almost certainly a condition caused by chronic sleep deprivation. The results don't speak for themselves at all. Read Matthew Walkers book and you'll have a better understanding of why we need 8 hours of sleep, and anyone saying otherwise is frankly misinformed.

I usually sleep around 6hrs on workdays. I need around 3-4 coffee / day, but not more :) I usually go to bed at around 2-3AM and wake at 8:30AM.

I can manage a job, side projects, girlfriend and social life. I'm not sure when will it hit back if it will ever.