I'm in a position where I need to buy a new Mac today. I'm looking at a MBA (13", i5, 256GB SSD) but have not decided how much RAM I should put on it. On my current Mac I notice every now and then a large amount of page-outs from memory but it is certainly not a constant issue, mainly only when I have several word documents or excel files open. As the RAM on the MBA is not upgradeable I'm trying to decide now to stay with 4GB or upgrade to 8GB to future proof it (2-3 years of use). The money to upgrade to 8GB is not the problem, but the added time in shipping the computer is. I move back to school next Tuesday and won't have my new mailbox number until then. So if I upgrade to 8GB then I'll have to have it shipped elsewhere and forwarded once I know my new mailbox. Sticking with 4GB will allow me to go to an Apple Store and pick it up today. Advice?