I'm in the market for more storage space and a faster computer, plus my 2010 MBA doesn't have all of the features of Mountain Lion. Am I better off getting a Retina MBP, or a new 13" MBA? I like the ultra portability of the MBA, and how light it feels on my lap, but I'm loving the 15" Retina Screen, quiet cooling fan, and specs of the MBP. How much heavier do you think the MBP will be?