I am either buying a retina MacBook Pro 13 or 15 inch or a MacBook Air, but can a MacBook Air handle Aperture photo editing with little to no lag? Or is a Retina MacBook Pro better for Aperture photo editing? I would also have up to 5 apps running at a time and I don't want the system to lag at all. So, if I were to get the air, I know for sure that I would upgrade the flash but should I also upgrade the Proceesor and the RAM? I have heard that the i7 proceesor makes battery life shorter. I do have a slight feeling that the pro is better for me, but I do want to know if the air could work for me. Thanks!