I used to use it. One thing I found is that when I use it, I would not get the receipt in my email. When I don't use it, I get the receipt in my email.

So, I don't use it.

I also don't stop at the desk. I just leave. There is no need to stop at the desk unless you are leaving a day early or wanting to extend your stay. The hotel knows you are checking out that day, and stopping at the front desk to tell them provides no additional value.