I've both driven a cab and used them on a regular basis. They CAN be unreliable if in a bad part of town. They can also be unreliable during special events like the ACL festival. This is why when you find a good driver you ask for his card, and tip well for good service. It is much better to be able to call your driver on his cell phone then rely on a third party.
Pros: Call a drivers cell phone, not the company.
Cons: Take your chances with the company
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