I open 7:30-5pm and that is long enough. I used to do 10 hr days, but not any more. There is no work-life balance with this job, so you've got to reclaim time to put your needs first.
I have 4 weeks vacation in my contract, but usually only take 2 weeks. When I go over 2 weeks, people give me a hard time-GIMME A BREAK! I'm too burnt out with only 2 weeks, so I'm going to start taking more, and not feel guilty about it. Over Xmas sounds like a great time to do it!