I've called Green Cab on a few occasions, all weeks apart at different times of the (week)day. Each time the driver arrived at the quoted time, was friendly, quickly got me to where I needed to be, and the rates are so damn cheap. Only downside is the hold times can be kind of long, but whatever. The consistently unfriendly and unpleasant person on the phone gets a pass--I'd hate working the phones at a place where they're ringing off the hook.