RoboDemo is certainly more powerful (feature-filled) than Camtasia, so it is harder to learn. But it is a great product. If you are planning on serving your Flash over the Web then RoboDemo is probably a better bet -- not just because it runs easily with your LMS. The screen motion capture system in RoboDemo is fundamentally different to that of Camtasia. Camtasia records the entire capture area for each frame, whereas RoboDemo captures only what has changed in each frame (and frequently this is just curser location). So RoboDemo's files are considerably smaller than Camtasias. I have also found Camtasias post-capture edit facilities to be rather crude.
RoboDemo will probably do what you need, and a lot more, and it will be relatively quick to learn. Buy it before Macromedia assimilates it and doubles its price.