Howdy, so I'm finally upgrading my early 2011 (17inch) 2.2 i7 which I have upgraded over the years to 16gb ram and a 512 SSD. The graphics card is the AMD HD 6750M, also I run a 24 inch cinema display as well. I'm a web developer running Virtualbox/Vagrant, Sublime, MAMP, & Photoshop mostly. My current machine is ok other than it's a BEAST, and it sounds like it's going to blast-off when I am running Virtualbox, so I figure it's time for an upgrade. I don't do any video production and very little gaming (my kids may jump on Minecraft from time to time), however I do want to make sure that I can play around with some WebGL stuff in the future and also be able to run one of these fancy 4K displays at some point. Soooo, my question is what is the cheapest configuration I can get (13 or 15 doesn't matter) while still having decent graphics and the ability to run a 4K display someday? Thank you so much!!!