Hi! I'm in the process of buying a new iMac. I'm a amateur photographer so it will used for light photo and video editing with Adobe Photoshop, Lightroom and iMovie. It will be also used for web browsing and word processing of course. I've decided to go with the 2.7GHz i5 version with 16GB of RAM but I'm not sure if I should go with 1TB Fusion Drive or a 256GB SSD. Right now I dont have enough data to fill the 256GB SSD. But I'm thinking that the 256SSD can be upgraded with a G-Raid 2TB eksternal drive or similar later/when needed. What do you think?