Please forgive my ignorance as it relates to the technical side of graphics, processors, et al. Although I was initially waiting for the release of tbMBP rev II, and still may; a recent situation has me considering the acquisition of a new MBP a bit sooner than later. I personally see the 15” as a better value overall however I do prefer the portability of the 13” selection. I’ve had a good number of MBP's at 13” - horsepower, or lack of, has never posed much of an issue for me but for the rare occasion that I create or modify videos. (I do see the potential for CAD/Modeling in the future, unlike the past) In contrast to the past while using my 13” machines, I have now introduced a monitor for use w/the laptop..and want to keep it that way. I settled on the LG 5K because it’s just a killer monitor. I have no current “plan” to add a second monitor, but stranger things have happened, because that’s how I roll. (I currently use a mid 2014 rMBP 13" i7) What advantage, if any, does the 15” hold over the 13” when it comes to driving this monitor? *If I go 15”, I would likely select the 512gb w/Radeon 455. 13”? - not quite sure how I’d spec that but, so far as I am aware, there are no higher spec’d options in the graphics dept for the 13", so it’s moot. Beyond graphics, are there any other advantages of the 15” vs 13” while using the LG 5K? Your guidance would be greatly appreciated.