Sony Xperia Z1 in for repairs 5X in first 10months

Within the first 10 monhs of this new contract phone the device was sent in 5 times for repairs. The problems ranged from non- responsive touch screen to a hanging operating system to phone restarting whenever it suited itself. Utterly dissapointed in my Xperia Z1 and that goes to SONY South Africa. Although the Vodacom assistants really tried to get me sorted - this ordeal cost myself and some staff members of Vodacom a lot af man hours, travelling, courier sevices and worst of all the loss of the use of a device I was paying for every month. I hereby plead to my service provider, Vodacom, to take this matter up with Sony SA. What happend to making sure the paying customer gets what he pays for? The IMEI nr for this particular device- ***! However this device came back on Friday for the last time - again via couriers- and has not shown problems yet - I am reluctantly awaiting. I have 4 Vodacom acounts and fortunately only one Sony device. Am I the only unhappy customer with Sony?