Yes, you must be disciplined about keeping all your records current. I have been using Quicken for years and I am glad - it tracks spending against budget, helps you allocate your spending into categories, allows me to download my credit card statement directly (so every transaction can be charged to the right category), etc. I still don't let it print my checks because I refuse to pay the high cost for the blank checks, but some people prefer the convenience.
I'm not anal about tracking the last penny, since I put the $50/week I pull out of the ATM into the category "spending money". But since I have been using it for a few years I can tell that the new windows in the house reduced my heating bill by about 20%, I can make sure I'm not spending too much on different things, and at income tax time I can transfer all my Quicken entries into TurboTax which saves me a lot of time. The only thing I don't like about Quicken is that every new release seems to take away features! That's why I still have the 1998 version (I think that's the one) on disk because it includes savings and retirement calculators which somehow disappeared from later versions - because it became a separate product they charged for.