Thanks to Erik Vlietinck, IT Enquirer, for reviewing Power Manager Professional 4. Erik's review neatly sums up Professional's strengths.
"Power Manager on its own is a powerful energy saving application for the Mac, that lives in your System Preferences panel. Power Manager is designed to save energy, but Power Manager 4.x and Power Manager Pro can actually do a lot more than only save energy."
-- Erik Vlietinck, IT Enquirer
You can download a 30 day demonstration of Power Manager and try it yourself.