ARS Technica took a look at Mac OS X font managers. Here's a snip from their review:
Well, it was a long time coming, but I've been through the trenches and come up, sucking chest wound and all, with the Ars review of font management programs. I've also succeeded in not completely losing my mind while the developers updated the apps, nullifying half my criticisms in the process. Giving a lot of time to these programs in a production setting is crucial to seeing how they perform on a daily basis, and I am confident I've thrown enough varied scenarios at each to find out where they succeed and fail..