All Day sits are the Best kind.
1. Comfort (1st & foremost)
2. Confidence in your stand site
3. Don't focus on the time you will be leaving (dark) hunt each hour for what it is.
4. I sit all day during Prime time (rut) increases your chances for action.
5. Some times of the season is just not productive here.
The best bucks I saw last year was between 10am and 2pm, and I killed my Mule Deer a little before 2pm.
Knowing those facts will help me sit all day this year!
Dan