[BrainInside]

Thanks for reply. I also will be relying mostly on OF. But, for example today I created few actions with OF and an event in iCal, basically for 1 task. I know on Wednesday I am driving to bring music books to a friend. I have to be at the place just before 5PM.
I created in iCal the event which takes 30 minutes. Now I see that it fits perfect to bring that just before gym.
To not forget I created action in OF with due date on Tuesday, 10:00PM, to remind myself to pack the books.
Another action in OF I created to text to my friend that I will be before 5:00PM at the place. Due date for that is 4:00PM on Wednesday.
In this example the due dates and times are when I need to take an action.

Since I look very often into my iOS OF, I know I don't have to do anything more to remember. My head is clean. I do not feel overwhelmed.
iCal is helpful to see everything. For example somebody would call me and ask me if I can do something. In the past I was saying "sure, I will be just after I will deliver books to my friend..." And then I had to skip the gym which I hate to do.
All my events like work, school, gym, and some other activities which occur on a specific date and time, or are repeatable, I prefer to keep in my iCal.
It is kind of new approach for me, but I feel that it works much better then old one, with iCal, OF only on my laptop and thousands of notes and notepads, everywhere.