I'm not sure whether to love National, or hate them because I still don't get how the Emerald Aisle is suppose to work. Yeah, I know it's supposed to be "pick a car and go" easy, but from where to I pick the car.

I'm Executive Elite status with National. If I book a midsize, know I can just take a car from the Emerald Aisle lot. But what if I book a compact or an Economy (smallest) or Compact (pretty near the same size as Economy)? Do I get to pick the next car size up, or what?

I've booked a Compact on a few occasions only to learn they're all gone. I was then instructed to take one from the Emerald Aisle (presumably without an extra charge).

So, what are your strategies for booking and selecting a car?