I will be entering uni this fall, and I can't decide between purchasing the 13 inch base model or 15 inch base model. I'll be using the laptop primarily for school work and video streaming. I might possibly use it to play an MMO. Do I need a 15" or will a 13" suffice? My current laptop is a 15" PC, and I like the size of the screen, but I've been using it as a desktop. I usually use my dad's 13" PC when I'm on the go. I'd like the 15" as it would be less strenuous on my eyes, but I'm concerned about portability... the size, not the weight.