Hi All, I recently upgraded from an Early 2011 MBP 13 inch to a Late 2013 Retina MBP 13 inch (2.6 GHz i5) with 500GB PCIe Flash, and 8GB RAM is there any major difference between this model and the 2014 2.6GHz one? I believe the graphics and stuff are the same? Are performance benchmarks the same how about in comparison to the 2015 Retina MBP? Thanks so much all!