I'm in my first year of university and I've decided that it's time to get myself a MacBook Pro. I've pretty much already decided that I want a 15" because I used something with an 11" screen throughout high school and it was super painful. The main thing is that I can't decide whether or not I should get the Retina MBP. I really really love the thinness of the Retina version and it's my main reason for wanting to get it, but the fact that you can't easily upgrade/replace a lot of things has made me consider going for the cMBP. I'd like something that will last me 4 years, since these things are pretty expensive. Thing is, I'm not sure if the difficulty of upgrading is really a big concern, as I'd only really be using the MBP for school stuff and light gaming... I don't really know what I would need to upgrade; I already have a desktop to do my heavy gaming and other stuff on. Although, I am pretty concerned about the fact that the rMBP's battery is glued in -- I'd like the laptop to last at least 4 years and it's cheaper to replace a battery myself. Which one should I get? Advice would be appreciated!