Do not buy iPhone from O2?

Never ever buy apple devices from O2, You know, why! Then read the following story:

I have a problem with intermittent unresponsive screen of my iPhone 6 plus (case number XXXXXX80 by apple support). After months of discussion and several trials, it was clear that it is a hardware problem. Then, Apple recommended contacting “O2” because I am in the second year of the Guarantee according to the EU law. Off course O2 service forwarded me to the insurance service. The insurance did not repair my phone, simply because I did not contact the insurance in due time. It is also my mistake, because I did not want to contact the insurance before being sure of the problem, hardware or software! At the end I have paid almost 1000 Euro and O2 did not repair my phone. Apple informed me that if I bought the phone directly from them, I had the chance now to get a new phone. Have you faced the same with O2?