I'm going to order my my MacBook Pro retina 15 from Apple this week. Before I do that, I need to order a leather sleeve, brief case and rubberized cover for front and back. I just want to know, if the early 2013 and late 2013 are exactly the same, or if Apple did change any physical dimensions or size or anything ? Or are they exactly the same, same size, same thickness and everything ? Let me know.