My experience with National has been generally fine. However, with my most recent rental I had an annoying revelation about the limitation of their service. Pulling out of the airport rental location having just picked up my car, still on the airport roadway, the car suddenly and completely died, leaving me in the middle of the road with a dead car, at probably one of the airport's busiest times. After much time and frustration trying to get some kind of assistance on the phone (their IVR system is a cycle of no-human-contact horror), I was told that they had no way to help me. I only wanted to have someone come pick me up and remove the road danger that the stalled car presented. So frustrating. When I finally made it back (by abandoning the car and walking to the terminal), there was an apology, but no offer of any kind to rectify or compensate me for my trouble and delay. Not happy.