I have a 13" rMBP which I love but am considering getting an external monitor because sometimes my neck hurts from looking down at the screen for long periods of time (vs I suppose the more ergonomically correct screen positioned where you can look directly at it). Some quick questions: 1) Can I use any type / brand of external monitor? 2) Will the monitor essentially mirror what's on my MBP? Can I essentially plug in my MBP, and then treat the monitor and a separate keyboard as a giant version of the MBP? lol. Thanks in advance.