DHL International parcel service
I was anxious about using an international courier after reading the reviews.  I had to because our Post Office is disfunctional.  
I was very impressed.  The price aside, which is very high, and the fuss made over sending children's books in a document pouch, the process went smoothly.  I handed the item in on Thursday and it was at its destination 4 days later.  The recipient received a number of sms notifications of the delivery.
So if I have the cash I will use them again