Lifetime Windows user here about to dive into the world of Apple. After doing some research, I'm stuck between two options in Apple's refurb store (hopefully both will be there by the time I make my purchase): whether to get the 6490 or 6750. Of course, the question becomes, what will I be using my Mac for? First off, I'm a CS student in college (so little to no GPU usage there). However, I also author DVDs and plan to run Bootcamp so I can play Flight Simulator X on it as well (from what I understand, FSX is more CPU than GPU intensive). Bearing these things in mind, is it worth the extra $300-$350 to get the 6750 or will I be just fine with the 6490? Thanks in advance for the advice!!