I am looking to buy a new Macbook Pro Retina and can't decide whether to go for 13" or 15". I don't really need portability as it will only leave the house about 4 times a year when i go on holiday, and then it will just stay in the caravan or lodge. I mainly just use it for surfing the net, emails, iPhoto and iTunes, nothing too taxing. The price difference between the two is quite a lot, so was wondering if it is worth paying the extra for what i do, both will have plenty of power for what i do, but will the extra real estate on the 15" make much of a difference, i don't mind paying the extra for the 15" if it is going to be worth it. What do you think.