We have used both Camtasia and Captivate in the past and have settled on Captivate as our main capturing software. It is much more efficient to capture screen by screen and the editing features are much more robust.

We do occasionally find ourselves filling in with Camtasia, but very rarely.

The most important reason to select Captivate is its fairly seamless integration with Adobe Connect Pro. Connect is one of Adobe's best kept secrets.