Still my #1 choice for my photography: wide gamut, true calibration, friendly pixel density.
2012 MBP 15-inch — Memory Bandwidth
Memory bandwidth correlates slightly with performance in memory-intensive compute jobs; it keeps the CPU cores humming efficiently. However, it is an interesting data point, but CPU caches largely hide the differences with most tasks.
Surprisingly, the MacBook Pro 15" model does not achieve the same memory bandwidth as the MacBook Pro Retina, even though both were 2.7 GHz models with the same chipset. Perhaps Apple’s soldered-on memory in the Retina model is somehow more efficient.