I have to agree with eserafini...
We had an inventory shipment coming from Minnesota to here in Ontario that was just a nightmare. Our supplier sent us a DHL airborne express tracking number. When the shipment never arrived, we entered the number on DHL's website and there it was. Showed the item having been picked up and in their hands. Well, 4 weeks later nothing arrived and we called DHL to see what the hold-up was (maybe stuck at customs?). Even with the tracking number, they could not located the package. They insisted that they never picked up the package in Minnesota (despite the supplier having a record of it, a DHL tracking number, and their own website confirming pick-up).
Eventually, my supplier re-shipped the order and it arrived. 3 months later, DHL delivered the original order with no explanation as to the delay. I've since confirmed that this was NOT a customs delay but in fact a DHL mix-up (for which they have no explanation).
The local DHL outlet also tends to be late with pick-ups. I don't know if this is true in other cities. If you call for a pick-up here and they tell you they will be there by 5pm tomorrow, add an extra day to it.
Lincoln