I faced problem with taxiforsure.com many a times.Very recently, we booked a cab for 2nd Nov14 at 5 am and I got confirmation that I will get cab details 30 mins prior journey, but I did not get any intimation till 4.30 am. When I called up, they said that the cab is on the way.
Again I called up at 4.45, they said that the cab got break down and no cabs are available at that moment. It was at 5 am in the early morning and what make sense saying that cabs are not available I dont understand.
I STRONGLY recommend not to go for taxiforsure as I said it is TAXIFORNOTSURE