I am deciding between 2 computers off of craigslist. One is a 13" late 2013 retina MBP with a 1TB SSD, 16GB ram, with a 2.8 ghz dual core i7 processor. The other is a 15" retina MBP with a 512gb SSD, 2.3 ghz i7 quad core processor and 16 GB of RAM. both have apple care remaining. Both are the same price (around $1600.) All things equal, I would prefer a 15" monitor, but this doesn't mean too much to me because this will be used as a "desktop" 95% of the time hooked up to an external monitor. The 1 TB drive is certainly very appealing to me. How do the 2.3 quad core vs 2.8 dual core stack up vs each other? I don't do much with resource hungry apps (little time on PS or video editing.) I would like to eventually hook this up to a 4k monitor down the road, once that becomes the standard. All those things considered, which would you go for?