I use Outlook Tasks in my work, and it really helps me to organise it. For now I'm starting to make use of To Do in my daily life, but there's no several of Outlook possibilities.
1) For example, I have everyday task, from April 1 to April 5. Today is April 3 - it is not possible to make a task for some reasons, but I want it to be continued until April 5. I can't remove just today's (April 3) task in To Do. If I'll delete it, April 4 and 5 tasks will disappear, so I must put a checkmark to complete today's task and then delete it (when I see, that April 4 task was synchronised and appeared above). In Outlook Tasks I can delete just an April 3 copy of my everyday task - that's all.
2) For example, I have an every week task (on Tuesday, Thursday and Saturday). Today is Saturday, but I can't make a task for some reasons. I'll do it on Sunday, so I change due date. Unfortunately, Sunday will be added to "Repeat" option (along with Tuesday, Thursday and Saturday), so I must complete my task on Sunday, wait for Tuesday and just then remove Sunday from "Repeat" option. In Outlook Tasks I simply postpone my Saturday's task to Sunday - "Repeat" option will not change.
3) For example, I have an every month task (15th day). Today is April 15, but I want to postpone my task to April 20, so I change due date. On April 20 I'll complete my task, however the next one will take place on May 20, not May 15. There's no such a problem in Outlook Tasks.