I have a pet peeve with taxi companies when their drivers accept calls that are way out of the district they're in.
I've seen them do it in the car while we're still ten minutes from my dropoff they're scoping the calls and bidding on jobs that are 15 minutes drive from my dropoff point.
It's a sort of "moral hazard" problem where taxi drivers have no incentive to do the right thing because its the company reputation that suffers.
I found this out a few trips ago when I called the company back and they told me that the driver had accepted the job when he was [the other side of town] and shouldn't be too far off now. Great. My email of complaint to the company received a "thanks for telling us, we'll handle it internally and don't expect a response".
So today after 25 minutes waiting I stood on a vantage point that showed the bus coming down the road and the turnin of my street where the taxi would come. A call to the taxi company gave me "he's close he should be there soon" and the race was on. The bus won. The cancellation came at the press of a button.
I'd recommend suburban taxis if you have a way to play a bus off against a cab. Their cancellation service is excellent.