I don't know if I am getting the short end of the stick here. I have 2014 iMac that has had it's set of problems. I have been told by Apple that the issues having with startup, bluetooth drops, facetime are all been fixed with Sierra, and not running that voids my AppleCare contract. So I upgraded, and the problems still exist. So AppleCare then had me wipe the iMac and just load the OS with no applications. Their test of functionality is that if I don't have any problems with my iMac running Sierra with no applications installed, then the computer and OS are all functioning perfectly and their support ends. A soon as I start to add applications to the iMac, then things start to go wrong. I want to use my mac for Photoshop, but when I load it, I start to get issues with Facetime and the camera not turning on. I personally don't like Safari, so I loaded Chrome and that caused issues with the bluetooth and the keyboard to randomly drop connection. The mouse does it too. I was told on AppleCare diagnostics that I am using too many unsupported USB devices. YES, I USE A FEW USB FLASH DRIVES. but as they are not official Apple products, then they want to shift the blame to me. Is Sierra that fragile that using anything that isn't stamped with an Apple Logo is taboo> And what good is a computer that you cannot use? Am I just getting jerked around by Apple?