It is relatively easy to use, although the learning curve is a bit steep because of its many features. It provides many of the features found in a CM, and others that CMs lack. It is the program I use because of its ability to handle repetitive tasks, a feature available on a more limited basis in the other two packages. Categories may be used to represent a project, status, or anything you choose including short messages. The menu bar allows you to search by assignees or categories.
Any scheduled item can be for a specified date, multiple days, or on recurring dates.
The recurring-item entry allows you to set the starting and ending dates so that the recurring item will not occur outside these dates. When a recurring item has been set up, any one item or all of the recurring items can be modified or deleted. Modification or deletion of an item in a recurring group does not affect the remaining items in that group. The other packages do not provide this flexibility. The task screen is very similar to the schedule screen.