i'm thinking of getting the rMBP 13" and i was wondering if it seems like just the flat out base model will be enough for me? pretty much the cheapest cheap. I will just be using it for twitter tumblr and maybe some light sims 4 gameplay. i'm planning on this for lasting me a while so how long do you think it will last with the low specs? and can i just use an external stroage if i need, if so what would you recommend?