My worst experience with Enterprise was at DFW. They insisted they see that I have auto insurance. I had to wait for them to contact my insurance company and wait for them to get a fax with the coverage. Then I get a busted up pickup truck. The savings over the other car rental companies was definitely not worth it so I banned them.

Then a couple years later I was flying to SWO (Stillwater, OK), and Enterprise is the only car rental company there. I was pleasantly surprised at the experience. It's so weird... where's there's competition, they suck, but when they are a monopoly, they're fine.