Thinking about buying a refurbished 27" iMac. The U.S refurbished store has two models I'm interested in. The first is a 2.9GHZ quad core 2012 model with 8GB of ram, 1TB 7200HD and a Nvidia geforce GTX 660M graphics card. ($1399) The second is a 3.2GHZ quad core 2013 model with 8GB of ram, 1TB 7200HD and a Nvidia Geforce GT 755M graphics card. ($1,529) I want to save as much money as I can so the cheaper the better. I do everyday tasks and don't do heavy intensive photography programs. I want a computer that will last me at least 4 years and will be gray for school work and to run a windows 7 VM.