I voted 8 - 10 but fall in the 7-8 camp. I have a very hard time functioning/keeping my eyes open if I get less than 7. I'm perfect on 8, but like to indulge in 10 every few weeks on a weekend morning.

I envy those who can function just fine on 5 hours. I could get so much more done and be less stressed if I had those extra 2 - 3 hours in a day.