When it's good, it's excellent. However, when they give you an estimated dellivery time, you cannot rely on it. In London the delivery is quick, whereas in Bournemouth my parcel arrived outside of the expected timescale, so I had left by the time it came. Overall it's an easy system, with good alerts and easy customer interface, but if you miss your date, you don't have much leaway: the parcels get sent back to sender much quicker than they get delivered!