What's the downside of using a retina MBP at a higher resolution than the best for retina display setting? I tried it out this weekend and didn't notice a difference-- what am I missing? Sme background: I have a 17 MBP that I love for the screen resolution but its huge and too heavy. I want something more portable but screen resolution matters a lot to me. I'd love to get the 13 rMBP but I'd run it at a higher res and want to know the downsides/if I'm making a mistake before I buy. Thanks.