I exchanged an m8 in a store that I had ordered through their website. The phone was bought through Next and I exchanged it on the 14th day. Whoever said they wouldn't exchange it for another m8 is wrong. If he is within his 14 days they will exchange it for another m8 or even a different device. After that they treat it as a warranty issue.
As a matter of fact, if you are within your 14 days and try to get a warranty exchange they won't allow you. They will tell you you are within your 14 days and should exchange the device.
How do I know this? With my m7 I ordered a 64gb in store.. It was defective.. Stores were not stocking the 64gb, only the 32.. I called to exchange it and they told me since I bought it in a store I had to exchange it in a store.. But no stores had any 64gb.. It was a hellish ordeal.. I had got fed up and tried to get the warranty department to give me a warranty exchange.. They did not allow me to... They said I was still within my 14 days. So if you're within your 14 days they won't even let you get a warranty exchange.
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