I posted my Mid 2012 15" rMBP (QC i7 2.3 8/256) on craigslist because a couple of weeks ago, I purchased a maxed out 27" iMac (QC i7 3.4 32/3TB Fusion/680MX 2GB). The dilemma I'm facing since I got the iMac is I feel like my 15" rMBP is too big and powerful (and superfluous) for my needs. Someone locally on craigslist is interested in trading their 13" rMBP for my 15" rMBP and said they would also pay cash in addition to that for the difference in value. Do you think a 13" rMBP would fit into my setup better? Also, is the 13" all that much more portable than the 15" or should I just go to the extreme with something like an 11" MBA? The 15" rMBP is AWESOME, don't get me wrong, it's just a much better primary machine than it is a secondary machine. I'm hoping the 13" rMBP would be a better secondary machine. I realize as a primary machine, the 15" rMBP is superior from a performance perspective in every imaginable way, but I would like to compromise some of that performance for more portability, as my iMac now takes care of 90%+ of my intensive applications/tasks.