The issue I have is when I have an early morning flight (say, before 0900). The HLE location near me doesn't open until 0630 so doing a regular one-way to the airport isn't going to work. In such cases, On Demand remains an option (although at that time of the day, I am probably going to take a cab).

I did my first On Demand rental with my Gold number entered in my profile this past Saturday; we'll see if the ZE1 points post.