Do not use AAD Planner myself, however, it did receive a positive review in the Dec/Jan 2006 ADDitude magazine ("To-Do Lists That Really Work" by Michael Sandler p 27). The author also gives "Life Balance" a big thumbs up.
Link to story:
You best solution may be to trial the program. ADD Planner provides a 90 day money back G/-, not quite the same as a free trial period, nevertheless a good offer. From the FAQ section they note that you can import/export between ADD Planner and Outlook so that may make the 'switch over' easier. They further state that future versions will allow "integration" between the 2 programs (a better solution in my opinion).