I've been sleeping a lot more than I normally do on weekdays lately, but usually sleep about 4/5 hours.
Holy cow. That's exactly how I feel when I get up. I uses to fall asleep on purpose in school because of this.I'd say 6. I don't fall asleep as soon as my head touches the pillow and I'm usually already awake before the alarm goes off in the morning. So I rarely get a "full night's sleep" in that sense. But I feel much better the nearer to 8 hours I get. If I get enough sleep I wake up feeling alert, invincible and ready to take on the world. It's a shame that feeling only lasts for an hour.