Depends on the person really. Some folks thrive under the pressure of knowing exactly what they need and can plan their round accordingly.
Some folks are exactly the opposite and prefer not to have the score they need hanging over their head. It allows them to be more carefree, play shots as they normally would play them instead of entering into Jean Van De Velde mode (over 10 years later and it still hurts just thinking about that guy).
Personally, waiting til the last minute has bitten me in the rear a few more times than I wish to remember, including one time when I ran out of time with a 4 foot putt left on 18. I dinged the putt and was promptly DQ'ed for being late. Oops.
To each their own. =)