The biggest advantage of National/Alamo IMO is being able to select your own car. I admit that it takes me an embarrassingly long time to pick my car
off of the aisle. My husband and I are both National Executive Elite (his earned, mine by signing up on a link I found years ago) so we book a midsize and can select anything from the midsize, fullzise or elite aisle.
The free upgrades are nice and worth a few $$ per day for me, but I am all about the bottom line. I remember being sooo nervous a few years ago about booking with Thrifty. I got an awesome rate of $79 for Christmas week and they upgraded us to a Taurus
. I have rented from Dollar and Thrifty many times since. The cars that I have been assigned by Dollar (and Thrifty) have been current, roomy and clean. IMO, there is really little difference between a Nissan Versa offered by Alamo/National and a Ford Focus offered by Dollar. It's a car that will get from from point A to point B. As long as my family and my bags all fit to/from the airport I'm good to go!