Printer's Apprentice is a useful tool for viewing and comparing your fonts and printing samples, and even for viewing font collections that you may or may not want to install. But even though it does a flawless job of installing and uninstalling your fonts, you need to be pretty organized to avoid getting in a real mess--and once you lose a font, Printer's Apprentice isn't much good at helping you find it. If you need (and can afford) a powerful font management tool, go for the professional-level FontExplorer X Pro, which is harder to learn, but manages your fonts with ease and poise, disabling unwanted fonts rather than uninstalling them.
On the other hand, if you're on a tight budget, have too many fonts, and need help organizing them, Printer's Apprentice is great at grouping and comparing fonts, and helping you decide which to keep and which to delete. It certainly works better than trying to delete fonts in Windows\Fonts manually. And if you regularly download font packs or have fonts stored on CDs, Printer's Apprentice is a cheap and easy way to view them and decide which to download...or not.