I am considering buying my first Macbook and am unsure what to choose. I have got as far as deciding I want a Pro and I want a small screen (13"). I am thinking about customising it to include 16Gb RAM instead of the standard 8Gb and i7 processor instead of the i5. My question is this - will I see £400 of benefit from the improved RAM and Processor, bearing in mind I want the smaller computer? Cheers!