Cut off time to start tourney..

For me, the best tourney's are in the 10 am-4 pm range. Playing well, making it to the final table, it's 3 or more hours. I like having the rest of the day to come down from tourney.
Many tourneys start in the evening. I try to have a rule: don't start a tourney after 8 pm. But rules are not set in concrete; I will start a tourney as late as 9:00 pm if its worth it to stay up till 12:30 am.
My "rules", what are your thoughts, cut off start times for tourneys, what times you do you play your best?

Whenever I start a tourney late at night I consider when it is starting, how much money I have to invest, how long it will take, what I have to do the next day, etc., etc. Then I say screw-it, I can work on 2 hours of sleep.

I have a cut off time of about 8pm for starting a tourney - anything later and I wouldn't be able to stay up and stay alert enough to see it all the way through.