I'm looking to replace a 2009 iMac with a 2TB drive in it. Looking at the Apple refurbs, I'm impressed with a ~$2000 rMBP that has a 512GB SSD on it. Now, my iMac would still stay at home and basically be a server for my Apple TV + local photos, but I'm wondering how difficult it would be to transition to a 512GB drive. Given that iTunes in the Cloud would let me access my purchased movies and music without local storage, and as of next year iCloud Photo Library will allow me access to my photos and home movies without eating up storage, I'm cautiously thinking that I might be able to do it. I could always get an external drive if I need to, but I'm no fan of carrying those things around with me. Also, am I correct in thinking that I could use my 2009 iMac (which has Mini Display Port but not Thunderbolt) in target display mode as an external monitor for the rMBP? Thanks all!