Looking to replace my 2007 Mac Mini HTPC with a newer model, but the used 2012s are scarce and expensive. I've seen quite a few 2011 models. Are they worth getting? I want to use it with OS X server, as a file server, Time Machine server, and Plex server. Would the 2011 model be good enough? Any reliability problems like failing GPUs (the discrete AMD GPU) or other known issues?