[yucca]

If you just need to keep track of time commitments, then OF + a spreadsheet should do the trick.

As ext555 says, if you need to precisely predict and schedule your available time then OP + OF may be worthwhile.

I own both, and am still undecided about utilizing OP as ext555 suggests. Not that the idea isn't valid; the returns just may not be worth the extra effort in my particular case. For managing a big project at work, OP is clearly a win . . . and that is true even though I do all my reporting via spreadsheets.