My wife's passion is photography. She currently has an older Mac Pro . Several months ago I upgraded to a nMP so its her turn to upgrade. Unbeknownst to her, I just bought her a semi-loaded retina iMac (I7, 1TB SSD,32GB, standard graphics card). She does not do any video. Did I do the right thing ? Whats the best external storage short of a Promise TB2 raid ?