I have owned the 13 and the 15. First I owned the 15 and I loved it! I did return it because it was creaking, had an uneven screen, and gmail wouldn't send emails, and also because they are no games I like for Mac.
Advantages of the 15: The big screen is simply amazing. You can put it on a Twelve South HiRise stand it can feel like a desk top. I loved the desk top feel and screen size AND the fact you could still put it away in a back pack and go to the library or wherever.
Disadvantage of the 15: None really. I suppose the only minor complaint is at night I lie down and keep the MBPr on my chest. It's definitely feels heavy and can get hard to breath sometimes. But that's hardly a problem at all.
Advantage of the 13: So portable! It's almost like carrying around an iPad. I can take it upstairs, downstairs, to the car, library, school, without thought because it's so light. It feels like I'm carrying a text book. Now, the 15 can also be taken to all the above places of course, and it's not that hard or anything, but the 13 is definitely more portable.
Disadvantage of the 13: You guessed it, I really miss the beautiful 15" Retina display. The 13" is not like a desktop. You will need an external monitor which I do have. Then it's more usable as a desktop.
Overall, I'd say the 15 is better, even though I own the 13, but I do believe it will become out dated quicker than the 13. I don't have proof but I believe Apple will find a way to make it more portable, lighter, and just handier overall.
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Good humour here
A free mac can never be a bad thing.
How did you get it for free??
