I'm thinking about buying the 13" Macbook Air and I found a pretty good deal on Amazon for a refurbished model ($800 for the base 13"). But Amazon only sells 4GB RAM models. If I decided that I need the 8GB RAM, then I will have to pay 240 dollars more for the $1040 8GB model on the Apple Store (Student discount). I'm mainly going to be using this for school and an Internship at Stanford in which I'm going to have to program in Matlab. Day to day things would include Chrome and Spotify. So should I shell out the extra 240 bucks for the 8GB model?