How well can the 13" rMBP handle video editing? I'm going to be in the market for an upgrade in the next 12 months, so I'm trying to decide what I want to get. I have a 15" rMBP right now, but really like the size and portability of the 13". I don't want to have issues editing though. I use FCP X mostly. I'm thinking for the price I pay for a 15", I could get a 13" and an external monitor for home. What do you guys think?