I'm about to purchase a refurbished iMac 27, late 2012. 3.4GHz i7, 1TB HDD, 1GB VRAM, 8GB RAM(Will upgrade via OWC).. There's another option of a 27 with 2GB VRAM and Fusion drive, but is roughly $400 more. I'm on a tight budget, so I was considering the first option. Then I thought, can I edit and run my editing programs off an external USB 3.0 SSD in a year or so? SSD will get cheaper an cheaper.. I figure after a year and a half of editing on a 7200rpm I'll be dying for an SSD. I'm in need of a camera backpack, tripod, and some other necessites. I could use some of the $400 saved.