At 4:52 I accidentally said that "to the constructor we will pass", but the observable is a function and not a class. So here we are passing the initial value to the function as a parameter. Sorry for this.
Functionality wise both are same but delegates may be better in cases where you are having the same functionality for multiple variables. With setters you need to write duplicate code but You can assign the deligate to a variable and then use the same variable as the delegates. This will reduce your code repetition.
