Having trouble deciding which is best for me. I don't need the computing power of either, however I would like a Retina display and something with more screen real estate than my 13" Air. I realize that the 15" Pro has the same effective resolution as my Air, but it can be scaled. I'm just torn about having something mobile. If I get the iMac, I'll keep the Air for now and maybe get a rMB in a couple of years. The other issue is price. I can afford spending $2099 on the iMac (not getting the base model because I don't want an HDD) with my student discount but I feel a little guilty about it. If I got the 15" Pro for $1899 I would sell my Air for around $500, so I would effectively save even more money. I've considered an external display but am not sold on it. Also, I feel like the 15" Pro is getting a little dated and the 5K might be a better investment. Any input? I feel like the 5K is the obvious choice, but I'm used to my main computer being a laptop and haven't had a desktop in probably a decade, however I don't need the portability at this point in time.