I'm currently evaluating options for the iMac and am curious as to what people would suggest here. I plane to do video editing as well as programming for a flight simulator game that I help produce. I have a corp discount on Apple that puts the i5 27'' with 2GB GPU ram at about the same cost as a refurb i7 27'' with 1GB GPU ram. What would you opt for, both in terms of longevity and the budget at hand? Thanks!